D4 A/C Compressor issue

[samandfee]

Hi Guys,

I have a 2013 D4 with 70k on the clock, relatively low and I am now having to replace the A/C Compressor. I feel this is a bit premature for a vehicle of this standard. Just wondered if any one else has had the same issue. Would appreciate feedback.

Cheers,

samandfee

[BradC]

Hi Guys,
I am now having to replace the A/C Compressor.

My first question is why? What were the diagnostic steps that led to the belief the compressor is toast?

[scarry]

ops,mistake

[samandfee]

Hi Brad
had a 400km round trip up the coast on the weekend just passed, hot air all the way up and back.
Nearly cooked the poor dog as well as me and the minister of war and finance.

RAC did an A/C service for $200 as I am a member I thinks that sounds OK….thought that was a good idea at the time, gave me back the car ….More Hot air.....took it back and they sent it to an A/C specialist...( could have been Fred Flinstone for all I know)

He determined it was the compressor Kapuut……...RAC said that will be an extra $160 thanks ….No way Hose said I...…...they took that on board reluctantly.
Back to an Aulro forum recommended LR people in Perth ( other than stealership) .....Their A/C guys think the same...…..So compressor it is then.

And here I am [bigsad]

[samandfee]

OOOOPs
Posted without looking at previous …….being dumb again......Doooooooh.[bawl]

[g5k]

If you search for the ac valve issue it may be what’s going. It’s an expensive fix still as there is a lot of labour involved in accessing it. From memory it’s a $600-800 job versus a $2000 job that was replacing compressor. I had my valve done about a year ago and has run flawless since. Need to do your own homework first to see if that is what is wrong in your case though. I’d find a LR independent workshop that also does a/c work.

[DiscoJeffster]

90% valve that is within the compressor however LR won’t replace only the valve as they only part swap the entire compressor. AC shops will swap the valve alone but want around $800 as previously stated.

[BradC]

A lot of generalisations in this post.

"Generally" an issue with the valve will start to cool within 10's of kilometers or if you really thrash it (lots of revs and vibration). You did 400km and it didn't cool, so that's probably not a good indicator for your car.

I've never seen a mechanic who does AC diagnose a faulty valve. They "generally" just replace the compressor.

*I've* never seen a completely stuck valve. If you are handy with a spanner, get the covers off on a hot(ish) day, set the thermostat as low as it will go and give the valve a couple of whacks with something heavy. See if it's an American valve (ie it responds to violence).

If you can unstick it and get plausibly workable cooling then you might get away with just a valve. "Generally" if its the compressor then the failing compressor will have spread aluminium dust through the system requiring extensive remediation in addition to a new compressor. You can tell when the valve comes out. If it's clean then you're ok. If it has a silvery sludge on it then it's pineapple time.

Most AC mechanics will put a gauge set on the car, run it up and look at the pressures. In the old days, a high low-side reading, and a low high-side reading just said "your compressor is dead", but these days with variable-displacement compressors it ain't necessarily so.

On the flip side, a variable displacement compressor is *always* circulating refrigerant. This stops the seals drying out (unless you are low on gas in which case your lubricant winds up in the evaporator and you lunch the compressor). So on the whole the newer compressors are more reliable. The displacement valve seems to be a real problem on all of them though. The yanks are up to speed on this. The last 3 valves I've bought have been from Amazon US.

Aussie tradies seem to be behind the curve and just replace compressors. Maybe there's more margin on a compressor.

I first learned about this stuff a few years ago when my wifes Golf developed "the delay". I got quoted a compressor, condenser, dryer, TXV and a very expensive hose/evaporator flush (just north of $2k). A $35 valve from Amazon US and a couple of hours in the driveway and it was sorted.

So... are you handy with a spanner?

[DiscoJeffster]

True Brad. I did very much generalise.

My old Golf that is now my mum's supposedly has the "black death" which is supposedly common within the Audi/VW fleet. It also take a long time to start cooling but eventually does, but poorly. In fact my own 2007 Audi also does this.

What are your thoughts on that issue? She was quoted an entire system replacement to resolve it as you stated, however I've also seen online people posting that despite being diagnosed with the plague, replacing the valve resolved it?

[DiscoJeffster]

As per the other AC thread, for those interested, geoffx19 found this related to the valve and its replacement

https://testing-public.carmd.com/Tsb/Download/106795/LTB00693NAS1

[g5k]

If you want to read on the valve for those that have suffered similar problems here is the thread I was referencing. In my case this was the fault (my LR Independent mechanic also diagnosed that as the fault as they also do a/c work).

(Thread is title d3 but I have a d4)

https://www.aulro.com/afvb/l319-discovery-3-and-4-a/244741-d3-air-con-trouble-2.html

[BradC]

True Brad. I did very much generalise.

My old Golf that is now my mum's supposedly has the "black death" which is supposedly common within the Audi/VW fleet. It also take a long time to start cooling but eventually does, but poorly. In fact my own 2007 Audi also does this.

What are your thoughts on that issue? She was quoted an entire system replacement to resolve it as you stated, however I've also seen online people posting that despite being diagnosed with the plague, replacing the valve resolved it?

It's one of those things. You don't know the condition of the system until you pull the valve. All the ones I've done have been valves. Haven't had to replace a variable-displacement compressor yet.

[Redtail]

Having been through the same experience myself in the past couple of weeks, I saw this thread: 2013 D4 Air Conditioner Issue (https://www.aulro.com/afvb/l319-discovery-3-and-4-a/268088-2013-d4-air-conditioner-issue-4.html), and now yours.

Symptoms in my 2011 (106K km) D4 were the same. No issue on cooler days, but struggled to maintain cold after 5 to 10 minutes when it was over about 35 degrees.

My local indie had a look. Checked the gas pressure - all good.
He then warned me that it could be the compressor, and that the refrigerant control valve (RCV) is within the compressor assembly, therefore a laborious ($$$) job to get it out. And once they did get it out, they'd check the compressor and evaporator unit too. Quote was around $3,500 or more depending on what needed replacing.

Thankfully, it was just the RCV. The compressor and evap were in very good shape.

New RCV fitted, evap cleaned, ducts disinfected, all reassembled for $1,300 - most of which was labour (they had it for the best part of two days).

[samandfee]

Thank you guys

And Redtail Yes thats the problem they say, these guys come highly praised from Kevin at Rovertech in Perth.

Its in today and pick up tomorrow ………….just under 1K and hopefully back to COOL air.[biggrin]

[Redtail]

Thank you guys

And Redtail Yes thats the problem they say, these guys come highly praised from Kevin at Rovertech in Perth.

Its in today and pick up tomorrow ………….just under 1K and hopefully back to COOL air.[biggrin]

Mine's too bloody cold now!
Funny how I'd gotten used to it. Hanging out for the weekend here to give it a proper test.

[Eric SDV6SE]

Touch wood, 185000km on my D4 and no such issues. AFAIK it has only been regassed once when the body was off for turbo replacement at ~165000km.

So far the A/C works as it should, I normally run it at 21-23deg and fan speed on low to mid.

Glad you got it sorted relatively quickly

[samandfee]

Hooray
Problem solvered.
$924.....One happy camper.......................cool as you like.[biggrin]

[DiscoJeffster]

Hooray
Problem solvered.
$924.....One happy camper.......................cool as you like.[biggrin]

Valve changed and regas?

[samandfee]

Hi discojeffster

Yes mate He said comp out, fix and replace re service and off you go .

[RobA]

Another most helpful thread. Our AC had a fit prior to Christmas after dragging the Q+ up through the hills on our way to Kingston on a reasonably warm day. Just started blowing warm air with temp set at 25C. Seemed to return to normal but yesterday it stared on the warm air thing again. All this in auto AC mode

Turned the temperature down to 22C from 26C and got cold air in manual mode

So our fault seems to follow this discussion just not completely sure. So would appreciate some feedback from the experts. Will need to check with our local indy's to see if either of them does AC or outsources

Rob

[g5k]

Another most helpful thread. Our AC had a fit prior to Christmas after dragging the Q+ up through the hills on our way to Kingston on a reasonably warm day. Just started blowing warm air with temp set at 25C. Seemed to return to normal but yesterday it stared on the warm air thing again. All this in auto AC mode

Turned the temperature down to 22C from 26C and got cold air in manual mode

So our fault seems to follow this discussion just not completely sure. So would appreciate some feedback from the experts. Will need to check with our local indy's to see if either of them does AC or outsources

Rob

Rob, I see you’re in Adelaide. If you take it to Sovereign in Kent Town they fixed mine by replacing valve. They do ac work too and can do some tests to try and diagnose.

Good luck.

Sovereign Auto | JAGUAR & LANDROVER, VW & AUDI specialists (https://sovereignauto.com.au)

[Petetheprinta]

Another most helpful thread. Our AC had a fit prior to Christmas after dragging the Q+ up through the hills on our way to Kingston on a reasonably warm day. Just started blowing warm air with temp set at 25C. Seemed to return to normal but yesterday it stared on the warm air thing again. All this in auto AC mode

Turned the temperature down to 22C from 26C and got cold air in manual mode

So our fault seems to follow this discussion just not completely sure. So would appreciate some feedback from the experts. Will need to check with our local indy's to see if either of them does AC or outsources

Rob

Hi Rob,
had exactly same problem. Went on for months. I also took to Sovereign motors in Kent Town who replaced the variable valve cost $960 😲but is now working fine. They told me very common fault. The valve just sticks and depending where it has stuck you get hot or cold air. Only had it done last week, they had another 3 booked in for same problem.
cheers
Pete

[RobA]

Guys thanks for those replies. The car is serviced at Sovereign so will book it in

Rob

[Litlbee]

I had issues with my aircon diagnosed as faulty compressor. Would not cool the car at all. Turned out to be the thermo fan on front of motor failed and caused the compressor to build up too much head pressure.

[mijango]

Can anyone recommend an independent in Sydney (ideally North) that can look at a/c system on my D4. It’s slow to cool and on long runs gets too cold. Sounds like the compressor valve from reading this thread

[imaz]

I think my D4 is doing this, or have some kind of blockage in the system. Initially thought a regas was required - Went to someone who regasses, however the Lo and Hi lines were not flowing through indicating possible blockage somewhere. The A/C is not cold now(was a tad cooler before attempting a regas). Somehow the rear unit is cooler.

So, maybe a condensor valve needs replacing? Compressor does click ON when I turn the A/C on.

Who is the go to guy in Perth? is it still Rovertech?

I did email my problem to AutoCool East Perth, they straight up said Big Work, $3000+ without looking at it yet. to replace compressor, condensor, rec dryer, tx valve , flush evaporator then regas & test.

I really cant bare a dash disassembly, been through that with my previous car JGC, whilst that was under warranty though.

[DiscoJeffster]

I think my D4 is doing this, or have some kind of blockage in the system. Initially thought a regas was required - Went to someone who regasses, however the Lo and Hi lines were not flowing through indicating possible blockage somewhere. The A/C is not cold now(was a tad cooler before attempting a regas). Somehow the rear unit is cooler.

So, maybe a condensor valve needs replacing? Compressor does click ON when I turn the A/C on.

Who is the go to guy in Perth? is it still Rovertech?

I did email my problem to AutoCool East Perth, they straight up said Big Work, $3000+ without looking at it yet. to replace compressor, condensor, rec dryer, tx valve , flush evaporator then regas & test.

I really cant bare a dash disassembly, been through that with my previous car JGC, whilst that was under warranty though.

Yeah Autocool are exxy. You will find cheaper elsewhere. They are assuming a complete compressor failure including Black Death presumably, hence the replacement of the majority of the system.

[josh.huber]

Yeah Autocool are exxy. You will find cheaper elsewhere. They are assuming a complete compressor failure including Black Death presumably, hence the replacement of the majority of the system.

Which is fair.. that's what mine was.. Dead comp.. grey death every where, massive strip to get drier off. Flush...

[BradC]

Yeah Autocool are exxy. You will find cheaper elsewhere. They are assuming a complete compressor failure including Black Death presumably, hence the replacement of the majority of the system.

I use them for had to get parts or custom hose work but the general attitude seems to be "we're booked up months in advance so we'll just quote a worst case and if you go somewhere else it's not a problem".

[PerthDisco]

Is this valve sold separately and is it located externally on the compressor? Does gas need removing to change it?

[imaz]

Is this valve sold separately and is it located externally on the compressor? Does gas need removing to change it?

I been told autocool sell the aftermarket valve for it.

It’s a b!tch to get to though.

lr061464

[DiscoJeffster]

Is this valve sold separately and is it located externally on the compressor? Does gas need removing to change it?

Valves are available. Only works occasionally. I changed mine and it didn’t improve it.

Yes degas and regas and as mentioned, it’s difficult to get to. Mine was changed when the body was off but it can be done from the wheel arch.

I’d save the money for a new compressor.

[imaz]

Thank you guys

And Redtail Yes thats the problem they say, these guys come highly praised from Kevin at Rovertech in Perth.

Its in today and pick up tomorrow ………….just under 1K and hopefully back to COOL air.[biggrin]


FYI - Kevin@Rovertech doesnt do this work now. I did contact them last Friday. They recommend the work to be carried out by AutoOWL.

I'm yet to decide how to proceed, since its inconvenient with work etc.

[imaz]

Update,

Went to another regas place(2nd time)who put the gauges on, read and found very high pressure in the lines, did not bother attempting to regas as doesn’t seem to think it’s required. Gauges needles were slow to move upon reving, and took a while stabilise when switched off.. Briefly determined compressor is functional. I mentioned the disco’s common to compressor valve failures, then told me there’s pressure in the system so appears to be fine. Suspected highly of the txv to look at.

I then went else where to a local auto elec(3rd time) near home and said to regas. Was told to leave it there for a couple hours as they had a few cars in. Came back to pick it up and there you go, it’s relatively cool (not typical A/C icy cold). So it’s now back to what it was a few weeks back, cool air and not just fan.

So clearly I’m partially unhappy with the outcome but I’d thought I would give it a week before complaining while I scratch my head. One thing I definitely noticed is for the past few months, I don’t get the water dripping from the A/C drain pipes.

Anyway, cut the story short - my viscous fan had been having occasionally ticking on cooler morning starts. Never thought about it much. Being circled with D4 friends, we compared the viscous fan airflow output when the cars idled side by side. Holy ****, mine was barely outputting much airflow at all, both cars had been driven a good 30km before the test. So, test swapped the viscous fans and guess what? High volume Airflow and A/C is now back in full force and Icy Cold!

1) I'm now wondering if the auto elec regas the A/C correctly when the viscous fan was not functioning correctly?
2) With a poor performing fan, what damages were I have caused with running the engine at higher temperatures...

[DiscoJeffster]

You won’t have caused any damage. If it had been telling you it was overheating and you kept going you would have, but you didn’t.

Interesting on the fan.

[BradC]

So, test swapped the viscous fans and guess what? High volume Airflow and A/C is now back in full force and Icy Cold!

For future reference, that would have been a 30 second diagnostic with an IID tool. Check the system high side pressure and the compressor valve position. With poor condenser airflow the high side pressure will steadily increase until it reaches the "limit" whereby the HVAC unit will throttle back the compressor.

If the compressor is duff or the valve is stuck, the valve position would be high with a low high-side pressure and high evap temperature.

Diagnosing the fan would have been the same. Check the fan RPM vs the fan PWM control.

[DiscoJeffster]

For future reference, that would have been a 30 second diagnostic with an IID tool. Check the system high side pressure and the compressor valve position. With poor condenser airflow the high side pressure will steadily increase until it reaches the "limit" whereby the HVAC unit will throttle back the compressor.

If the compressor is duff or the valve is stuck, the valve position would be high with a low high-side pressure and high evap temperature.

Diagnosing the fan would have been the same. Check the fan RPM vs the fan PWM control.

Hi Brad
How does one distinguish between the pressure limit being met and the compressor throttling back versus normal operation? What does normal operation look like? I’m interested to take a look at mine.

As for the fan you’re saying to check actually rpm versus commanded rpm presumably? You’d think there would be a DTC flagged if it’s operating outside of commanded [emoji2369]

Either way, I’m going to do this diagnosis on mine, though I’m pretty sure at 300k km my compressor is simply shagged [emoji846]

[imaz]

For future reference, that would have been a 30 second diagnostic with an IID tool. Check the system high side pressure and the compressor valve position. With poor condenser airflow the high side pressure will steadily increase until it reaches the "limit" whereby the HVAC unit will throttle back the compressor.

If the compressor is duff or the valve is stuck, the valve position would be high with a low high-side pressure and high evap temperature.

Diagnosing the fan would have been the same. Check the fan RPM vs the fan PWM control.

You are absolutely correct! Here is the error.

https://uploads.tapatalk-cdn.com/20211017/c47a0adbe1c2bc4c8b5ccd468fa43b54.jpg

[josh.huber]

Any aircon bloke should have picked that up..I feel for ya mate.. As soon as you see high head pressures you put a hose on the condenser and see how it reacts.. If il the vent temps and pressure drops. It's pretty simple. Good pickup..


Actually after a vac, when putting the right amount of gas in. Old mate should have known the head pressures could only be caused by the condenser, get your money back. He's an idiot.

[scarry]

Any aircon bloke should have picked that up..I feel for ya mate.. As soon as you see high head pressures you put a hose on the condenser and see how it reacts.. If il the vent temps and pressure drops. It's pretty simple. Good pickup..


Actually after a vac, when putting the right amount of gas in. Old mate should have known the head pressures could only be caused by the condenser, get your money back. He's an idiot.

Exactly.

High head pressures isnt rocket science,for a tech or techs,in this case, that are experienced and doing this sort of stuff all the time,its an easy diagnosis.

[imaz]

Any aircon bloke should have picked that up..I feel for ya mate.. As soon as you see high head pressures you put a hose on the condenser and see how it reacts.. If il the vent temps and pressure drops. It's pretty simple. Good pickup..


Actually after a vac, when putting the right amount of gas in. Old mate should have known the head pressures could only be caused by the condenser, get your money back. He's an idiot.

First two were free as no regas was not done.

[josh.huber]

First two were free as no regas was not done.

That's good it didn't cost you a cent then mate, great result

[BradC]

As for the fan you’re saying to check actually rpm versus commanded rpm presumably?

Yep. The DTC was a bit of a giveaway though.



How does one distinguish between the pressure limit being met and the compressor throttling back versus normal operation? What does normal operation look like? I’m interested to take a look at mine.

174484

The 3 bits of information you want are :
"Air conditioning system pressure" - The high side pressure measured in the liquid line between the condenser and evap.
"Evaporator sensor" - Temperature sensor on/in/by the evaporator.
"Compressor/motor current" - Not current at all, but some form of measure which relates to the RCV position. I see 0 when it's switched off, ~240 when it's flat out and it idles somewhere around 132.

If the evap temperature is above > 5.5 degrees, the ECU will generally open up the RCV to increase cooling. The evap temp seems to sit between 4.5-5.5 degrees. That can vary as the unit manages the cabin humidity also, but that's "generally normal" for my D3.

The system pressure directly correlates to the condensing temperature using the r134a PT curve. 7.7 bar is roughly 30C.
The manual says ~33Bar is the safety limit which is ~90C at which point it will try and set the compressor to minimum displacement.

So from a diagnostic point of view, you want to see the evap temp low and steady and the compressor not commanded flat out.

[DiscoJeffster]

Cheers Brad.

So I went for a pootle around the streets and generally saw 1 deg on the front condenser. Got the rear down once I engaged the rear ac (obviously), and saw max 200psi pressure with around 170psi being fairly average.

Outside temp a mild 23 so it wasn’t having to do anything today.

Mine seems to show a very different view of “motor current” with it never going above 0.6 whatever it is.

It was cold in here. Looking forward to trying when it’s playing up. Sometimes I find I have to turn off the AC and back on again for it to start cooling again. Ot would be interesting to see the stats when it’s doing that.
https://uploads.tapatalk-cdn.com/20211018/d22094aa814f8adac3767aa8dbfee8f6.png

[scarry]

Those head pressures at 23 degrees ambient seem a tad high for 134a,but maybe OK.
They depend on quite a few variables.
That’s liquid line pressure,so the actual head pressure will be slightly higher,depending on condenser pressure drop.

It would be good to revisit the pressures at ambients of 30 to 35 degrees,and see what they are,while driving.At idle they are often higher due to no ram air,although with an electric override on the viscous radiator fan,it may cut in and reduce the HP.

[DiscoJeffster]

Example of it just not working. Ambient coming through the vents. Was about 5-10 minutes after starting after being parked in the cool underground.

Effectively my interpretation is the compressor was commanded to max output (0.75 is the highest compressor value I’ve seen) but the pressure was the lowest indicating the compressor wasn’t actually able to action what was being requested.

No cooling occurring as seen by the evap temp.

I had the compressor valve changed (well I provided it and asked for it to me changed) two years ago, but effectively this random not enabling issue persists.

I should add “commanded 20deg C” on the HVAC

[https://uploads.tapatalk-cdn.com/20211022/40698553581fd7b4bf2aa132f8f05a51.png

[BradC]

Yeah, condensing temperature of ~27C. The compressor is at minimum displacement. If it's not the valve, then it *has* to be the compressor. Even if a TXV was jammed open I'd expect to see more head pressure than that.

If it was electrical I *assume* (dangerous, I know) the HVAC ECU would be bitching about the valve circuit being open, to ground or high.

[imaz]

That's good it didn't cost you a cent then mate, great result

Just ordered a new viscous fan from UK. Should be here in a week. $500 landed and taxes. Another disco fella purchased one last week from the same online seller and we both inspected it, looks to be identically genuine with the serial scrubbed out? Anyway, should be good.

My Aircon is still cold, down to 8.2c at the vent from what I could measure with the test viscous fan I have.

https://uploads.tapatalk-cdn.com/20211022/838f4eafcdfec0eb061be78b62ce1207.jpg

[imaz]

Those head pressures at 23 degrees ambient seem a tad high for 134a,but maybe OK.
They depend on quite a few variables.
That’s liquid line pressure,so the actual head pressure will be slightly higher,depending on condenser pressure drop.

It would be good to revisit the pressures at ambients of 30 to 35 degrees,and see what they are,while driving.At idle they are often higher due to no ram air,although with an electric override on the viscous radiator fan,it may cut in and reduce the HP.

Where is the resisters on the viscous fan circuit? These can fail if the disco is reliant on one.

[scarry]

Where is the resisters on the viscous fan circuit? These can fail if the disco is reliant on one.

Sorry,cant help.
Hopefully someone else can chime in.

[BradC]

Where is the resisters on the viscous fan circuit? These can fail if the disco is reliant on one.

What resistors? The Viscous fan is directly PWM controlled from the ECU and has a return signal to indicate the RPM.

[DiscoJeffster]

You have a new fan coming. It’ll fix your issue. Don’t worry, be happy

[imaz]

You have a new fan coming. It’ll fix your issue. Don’t worry, be happy

https://uploads.tapatalk-cdn.com/20211028/83b065f341d829fb7624e13211233ef2.jpg

Under 7 days delivered from UK, happy days.

[imaz]

https://uploads.tapatalk-cdn.com/20211028/83b065f341d829fb7624e13211233ef2.jpg

Under 7 days delivered from UK, happy days.

Looks like the weather is getting warmer ~25c and it’s gone to ***** again. Eventually gets cooler and now as low as 15c at the vents whilst driving highway speeds, and even that it tapers off. The strange thing is, the rear AC is more colder than the front ever does, and the rears consistent - it’s the same compressor!

Guessing a compressor is likely? Could it be anything else? Txv? The Autoelec who did the regas found it strange behaving during the second diagnosis he did this week. Pointed that compressor would be recommended.

AC Pressure sits at a shy of ~900kpa and as I rev and hold to around 1200rpm, the pressure will go up to around 1.2MPa and the system will start to be cooler at the vents.

Looking at the SDD, max AC pressure is around 3.1MPa, so I would be happy if the AC system pressure sat around 1.5MPa idled...

Anyone have any reading of a working AC system?


https://uploads.tapatalk-cdn.com/20211106/fd3e84d8e612f15e4d3073e32d6d304a.jpg

I also did a evaporator clean using that HVAC Coil cleaner Pro foam spray by CRC and flush with water through the drain tubes on the front dash , and through the blower access for the rears.


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[scarry]

That evap was very dirty,usually that drops off the airflow.

Have a good look at the condenser,is it clean as well?

You need a good AC guy to look at it,one that has done LR work before,could be numerous things that maybe causing the problem.

I wonder if Dazza on here knows a good AC guy,i believe he is in Perth?

[josh.huber]

These variable compressors can be a pest to diagnose as they don't have an over ride function on the scan tool (that I have found anyway) .
you are monitoring the current to the valve. That will at least give you insight.

If you start the car up and the AC system is set to say 17 and is 30 ambient out, it force it to full stroke, try not to do it in the shed. They have a sunlight intensity thing on the dash, if it goes to full force and still givers that low that's an issue.

My compressor was full of grey death..

I'll go start mine and get you some idle figures

[josh.huber]

https://uploads.tapatalk-cdn.com/20211106/f78138b323e5f257f55382e45ff14be2.jpghttps://uploads.tapatalk-cdn.com/20211106/0652b45342b36719cc75e1f6ece118c7.jpg

That's with the car off,

With it on and cooling

https://uploads.tapatalk-cdn.com/20211106/d9140c9c87e1d1a3c774bb5958b3f569.jpghttps://uploads.tapatalk-cdn.com/20211106/74a357f102d8fa0c4e44af54e45d47c6.jpg

I used my gauges to check the sensor for accuracy

With me driving it..I added road speed to try and help ya. Also note the different compressor motor current. The first one I didn't pick up was the wrong item. Sorry..

https://uploads.tapatalk-cdn.com/20211106/f68769826f3fc17a668a30d509fa48d2.jpghttps://uploads.tapatalk-cdn.com/20211106/079a0a99845295bccd61bd4c418c00d1.jpg

What I remember from diagnosing mine was the compressor current was always at .750amp trying to get a response, now it seems it's never there, even on low this morning never about .6amp.

Happy to take more information this arvo when I finish this job im on and traveling home.

[DiscoJeffster]

In my opinion experience, the issue is the compressor/valve control combo just stops working randomly. Mine has figures like yours Josh when working but the time it went warm and I got the GAP onto it, you could see the ac was being commanded to full, but nothing was happening.
The figures when that happens are below. And note, mine has a new valve in it so that wasn’t a fix for me. The frustrating bit is when it works, it’s fine.

https://uploads.tapatalk-cdn.com/20211106/b02bb72f2efda5962f5462ad01323a4f.jpg

[imaz]

Gonna be an interesting weekend, gonna tackle this. Will get someone to degas and evacuate the lines tomorrow.

Local supplier has the compressor in stock for $645. Will also change the receiver dryer also.

https://uploads.tapatalk-cdn.com/20211110/4b5cd5a11850989d7c27ca8464f105fe.jpg

[josh.huber]

Gonna be an interesting weekend, gonna tackle this. Will get someone to degas and evacuate the lines tomorrow.

Local supplier has the compressor in stock for $645. Will also change the receiver dryer also.

https://uploads.tapatalk-cdn.com/20211110/4b5cd5a11850989d7c27ca8464f105fe.jpg

Hey bud, if you want to call me that's cool, pm me and I'll send you my number.. That job is fresh in my mind and there are some things you need to do.

If you don't that's cool..

But you must flush it properly. The tooling is cheap. You also need to add oil to the compressor as it doesn't have enough in it especially with rear air

[imaz]

Hey bud, if you want to call me that's cool, pm me and I'll send you my number.. That job is fresh in my mind and there are some things you need to do.

If you don't that's cool..

But you must flush it properly. The tooling is cheap. You also need to add oil to the compressor as it doesn't have enough in it especially with rear air

Yeh cool, pm and I shall call.

I was reading the sanden booklet and did notice oil recommendations, and compressor was pre-oiled, but as you mentioned is not enough for dual AC’s. I didn’t see where to add the oil, some compressor’s have an oil catchment from videos I had seen.

[josh.huber]

Yeh cool, pm and I shall call.

I was reading the sanden booklet and did notice oil recommendations, and compressor was pre-oiled, but as you mentioned is not enough for dual AC’s. I didn’t see where to add the oil, some compressor’s have an oil catchment from videos I had seen.

Goes in through the plug in the Center of the body. There is a post from me somewhere on here about how much to put in. Even without rear air it's not enough.

[imaz]

Goes in through the plug in the Center of the body. There is a post from me somewhere on here about how much to put in. Even without rear air it's not enough.

Old compressor is out, here is the oil. Looks ok to me, no traces of anything metallic that I can see.


The wire to the electronic valve might have a pinch.

https://uploads.tapatalk-cdn.com/20211113/8d715d0dab372c6b98a2172774fb5023.jpg

https://uploads.tapatalk-cdn.com/20211113/56e7cbae123d196a85a7fdd6badbfaa1.jpg

[imaz]

Short update, fixed.

Regassed to 900g, outside temp today 27c, while inside cabin is ~4.1c.

New compressor is silent in that no clicks when engaged ON/OFF when you hit the A/C button.

End.

[Eric SDV6SE]

Short update, fixed.

Regassed to 900g, outside temp today 27c, while inside cabin is ~4.1c.

New compressor is silent in that no clicks when engaged ON/OFF when you hit the A/C button.

End.
Job well done imaz

Interesting, so the clicking noise is an indicator that something is wrong? 217000km on original compressor, had it regassed earlier this year as a preventative measures and still cooling as usual.

[imaz]

Job well done imaz

Interesting, so the clicking noise is an indicator that something is wrong? 217000km on original compressor, had it regassed earlier this year as a preventative measures and still cooling as usual.

No idea, I can hear it slightly click now. Perhaps it’s a new compressor just burning in.

At the price I got the new part for, there is no reason to swap the Valve.

For reference here are the stats of the functioning system at idled/parked.


https://uploads.tapatalk-cdn.com/20211115/e05e664391c685699782cc6744e3fb81.jpg

[shack]

A lot of generalisations in this post.

"Generally" an issue with the valve will start to cool within 10's of kilometers or if you really thrash it (lots of revs and vibration). You did 400km and it didn't cool, so that's probably not a good indicator for your car.

I've never seen a mechanic who does AC diagnose a faulty valve. They "generally" just replace the compressor.

*I've* never seen a completely stuck valve. If you are handy with a spanner, get the covers off on a hot(ish) day, set the thermostat as low as it will go and give the valve a couple of whacks with something heavy. See if it's an American valve (ie it responds to violence).

If you can unstick it and get plausibly workable cooling then you might get away with just a valve. "Generally" if its the compressor then the failing compressor will have spread aluminium dust through the system requiring extensive remediation in addition to a new compressor. You can tell when the valve comes out. If it's clean then you're ok. If it has a silvery sludge on it then it's pineapple time.

Most AC mechanics will put a gauge set on the car, run it up and look at the pressures. In the old days, a high low-side reading, and a low high-side reading just said "your compressor is dead", but these days with variable-displacement compressors it ain't necessarily so.

On the flip side, a variable displacement compressor is *always* circulating refrigerant. This stops the seals drying out (unless you are low on gas in which case your lubricant winds up in the evaporator and you lunch the compressor). So on the whole the newer compressors are more reliable. The displacement valve seems to be a real problem on all of them though. The yanks are up to speed on this. The last 3 valves I've bought have been from Amazon US.

Aussie tradies seem to be behind the curve and just replace compressors. Maybe there's more margin on a compressor.

I first learned about this stuff a few years ago when my wifes Golf developed "the delay". I got quoted a compressor, condenser, dryer, TXV and a very expensive hose/evaporator flush (just north of $2k). A $35 valve from Amazon US and a couple of hours in the driveway and it was sorted.

So... are you handy with a spanner?Brad.... When the A/C compressor is on the car, how viable is it to get to the valve?
Is it basically a compressor out job? If so may as well just do that, but of it can be done through "keyhole surgery" it's probably worth a punt.

[scarry]

. So on the whole the newer compressors are more reliable. The displacement valve seems to be a real problem on all of them though. .

Many new vehicles still use the standard compresser,no displacement valve,and they are extremely reliable.

Not having a displacement valve is one less thing to fail,i suppose.

Compresser seals very rarely,if ever fail these days,and the seals on the hoses,and the hoses themselves are very good quality.

Its the poor quality evaporators and condensers that cause most of the issues these days, in some vehicles.

[BradC]

Brad.... When the A/C compressor is on the car, how viable is it to get to the valve?
Is it basically a compressor out job? If so may as well just do that, but of it can be done through "keyhole surgery" it's probably worth a punt.

When I wrote that post my experience working with the mechanics in and around the disco donk was "a bit less" that I have now. I can't see a viable route to do just the valve on the my D3, and on that basis if I were pulling the compressor I'd be replacing it with new. All the other cars I've done it on have had a clear and relatively easy route to the valve.

I just grabbed the borescope and went for a poke around just to make sure, and I reckon there's a clear path to the valve, but it looks like to get there you'd need to remove :

The passenger front wheel
Upper suspension arm
Air bag
Heat shields
Turbo discharge pipework

And a few other miscellaneous bits.

You might get there with less if you can bend your arm like I can my borescope, but I've never seen it done in any manner that didn't require the assistance of an orthopedic surgeon to put it back together.

So, it's probably a compressor out job on the disco.

[shack]

When I wrote that post my experience working with the mechanics in and around the disco donk was "a bit less" that I have now. I can't see a viable route to do just the valve on the my D3, and on that basis if I were pulling the compressor I'd be replacing it with new. All the other cars I've done it on have had a clear and relatively easy route to the valve.

I just grabbed the borescope and went for a poke around just to make sure, and I reckon there's a clear path to the valve, but it looks like to get there you'd need to remove :

The passenger front wheel
Upper suspension arm
Air bag
Heat shields
Turbo discharge pipework

And a few other miscellaneous bits.

You might get there with less if you can bend your arm like I can my borescope, but I've never seen it done in any manner that didn't require the assistance of an orthopedic surgeon to put it back together.

So, it's probably a compressor out job on the disco.Well that's a depressing read, thankyou very much though for going to that effort!!

Much appreciated.

[DiscoJeffster]

I had my valve changed and it didn’t help the randomness of my AC where it just effectively stops working. I find if I turn it off on the dash for 10 second and on again it wakes up and starts cooling.

I’d just do the compressor and be done with it next time.

[shack]

Definitely want the whole thing changed, was just looking for a shortcut... But that might be too much to ask for on an L319.

[ATH]

Without reading the whole thread it seems to me that the aircon fitted to Landies is problematic. Just had a new compressor fitted to our 2016 D4 at just over 100K and our Puma had it's fail at around 150K. Over 3K to fix both times but at least the extended warranty paid for the D4s.
AlanH.

[letherm]

Without reading the whole thread it seems to me that the aircon fitted to Landies is problematic. Just had a new compressor fitted to our 2016 D4 at just over 100K and our Puma had it's fail at around 150K. Over 3K to fix both times but at least the extended warranty paid for the D4s.
AlanH.

Had mine replaced in my 2013 D4 last May. Can't give an exact figure as I had a service and remap and EGR blank at the same time. It would have been over $3000 as Alan has said. PITA job by the sound of it.

Martin

[PerthDisco]

A video for future searchers:

How to replace AC compressor on Land rover discovery 3 2007 turbo diesel - YouTube (https://youtu.be/D8GKnZwW5Ac)

[BradC]

A video for future searchers:

How to replace AC compressor on Land rover discovery 3 2007 turbo diesel - YouTube (https://youtu.be/D8GKnZwW5Ac)

That sounded like a rambling 3 minute narration of the steps listed in the service manual plus a few other bits he took off to get in there.

[PerthDisco]

That sounded like a rambling 3 minute narration of the steps listed in the service manual plus a few other bits he took off to get in there.

I find if I read about any job in the service manual it always seems mission impossible but when I see a video I always feel like it’s doable.

Monkey see monkey do

[imaz]

Well that's a depressing read, thankyou very much though for going to that effort!!

Much appreciated.

Airbag?

It’s relatively cheap to replace the compressor, attempting to replace the valve isn’t worth the time once you know how much is involved to remove and replace the comp.

[imaz]

That sounded like a rambling 3 minute narration of the steps listed in the service manual plus a few other bits he took off to get in there.

You need a hand of a midget to work around crap in that area. The video makes it look easy, but you are literally working blindly.

[shack]

Airbag?

It’s relatively cheap to replace the compressor, attempting to replace the valve isn’t worth the time once you know how much is involved to remove and replace the comp.Hence my question...

[BradC]

Airbag?

Otherwise known as the "air spring" or the "rubber bellows around the shock absorber" or the "****ing rubber bastard with the leak".

[imaz]

Otherwise known as the "air spring" or the "rubber bellows around the shock absorber" or the "****ing rubber bastard with the leak".

No need to remove.

[BradC]

No need to remove.

To get to (and remove) the valve without removing the compressor?

[imaz]

To get to (and remove) the valve without removing the compressor?

You can try, but you have the chassis / airbag mounting and UCA which largely blocks your entire view of the comp.



https://uploads.tapatalk-cdn.com/20211228/0c454af494da68eab5ed09a12526ed24.jpg

[DiscoJeffster]

You can try, but you have the chassis / airbag mounting and UCA which largely blocks your entire view of the comp.



https://uploads.tapatalk-cdn.com/20211228/0c454af494da68eab5ed09a12526ed24.jpg

So why two posts up did you say “ no need to remove”? Do you mean you don’t have to disassemble the strut, but will need to remove it?

[josh.huber]

I've never done the valve, but you can definately do the compressor without touching the strut at all.

[josh.huber]

I've never done the valve, but you can definately do the compressor without touching the strut at all.

Which means you can do the valve in there too I guess

[BradC]

Which means you can do the valve in there too I guess

Potentially. The valve is quite long and has to withdraw out straight, not to mention getting to the circlip holding it in. I just poked the camera around and figured if you were going to do it, removing the upper arm and airbag would make it easier.

It's all theoretical really as given the difficulty of getting in there you'd be better replacing the compressor.

[imaz]

Potentially. The valve is quite long and has to withdraw out straight, not to mention getting to the circlip holding it in. I just poked the camera around and figured if you were going to do it, removing the upper arm and airbag would make it easier.

It's all theoretical really as given the difficulty of getting in there you'd be better replacing the compressor.

Replace the compressor, it’s cheap. Stuffing around with the valve, refilling, not worth the effort for trial and error.

[imaz]

So why two posts up did you say “ no need to remove”? Do you mean you don’t have to disassemble the strut, but will need to remove it?

I implied that I don’t think you can remove and gain much space. Drop the comp and do the work on the bench. Better yet replace the comp.

[josh.huber]

All in all. It's a **** job. All jobs on modern cars are

[haydent]

Gonna be an interesting weekend, gonna tackle this. Will get someone to degas and evacuate the lines tomorrow.

Local supplier has the compressor in stock for $645. Will also change the receiver dryer also.

https://uploads.tapatalk-cdn.com/20211110/4b5cd5a11850989d7c27ca8464f105fe.jpg

where can i get an ac compressor like this in australia for less than $1k ??

[DiscoJeffster]

where can i get an ac compressor like this in australia for less than $1k ??

Rockauto in the US

[DiscoJeffster]

Rockauto in the US

Sorry, you’ll struggle to get good prices retail in Australia

[haydent]

Sorry, you’ll struggle to get good prices retail in Australia

figured and prepared to order it from uk, but it seemed like from that post it could be done, but maybe they are in US

[josh.huber]

figured and prepared to order it from uk, but it seemed like from that post it could be done, but maybe they are in US

The us stuff is all for the petrol V8 or v6 supercharger.

Try Napa Auto parts

[PerthDisco]

The us stuff is all for the petrol V8 or v6 supercharger.

Try Napa Auto parts

Or Parts Souq but lots of ancillary stuff is common.

[DiscoJeffster]

The us stuff is all for the petrol V8 or v6 supercharger.

Try Napa Auto parts

Yeah. Good point that.

[ATH]

I've got a Sanden comp off a Puma 2.4 which had the internal seals renewed some 3 -4 years ago. Since then I've had it in the shed with bungs in the inlet/outlet openings and boxed to keep it in good nick just in case I needed it.
However times have changed as will be the vehicle in the sometime in the future new car world, and I'm clearing out stuff I no longer euire.
I'll flog it off for what it cost me for the seals ....approx 200 bucks.
AlanH.

PS. I sacked the so called aircon bloke as he was an incompetent who'd never worked of anything other than buzz boxes and didn't know one end of a Defender from the other. :)

[LuckyLes]

I've got a Sanden comp off a Puma 2.4 which had the internal seals renewed some 3 -4 years ago. Since then I've had it in the shed with bungs in the inlet/outlet openings and boxed to keep it in good nick just in case I needed it.
However times have changed as will be the vehicle in the sometime in the future new car world, and I'm clearing out stuff I no longer euire.
I'll flog it off for what it cost me for the seals ....approx 200 bucks.
AlanH.

PS. I sacked the so called aircon bloke as he was an incompetent who'd never worked of anything other than buzz boxes and didn't know one end of a Defender from the other. :)

The above compressor will not fit a D4, and if you sacked the guy, how much credence would anyone put in his ability to successfully replace the seals.

[ATH]

The above compressor will not fit a D4, and if you sacked the guy, how much credence would anyone put in his ability to successfully replace the seals.
He didn't. He got a company in E.Perth to do it and they were/are good at what they do apparently. I'm searching for the invoice now.....
AlanH.

[BradC]

He didn't. He got a company in E.Perth to do it and they were/are good at what they do apparently. I'm searching for the invoice now.....
AlanH.

That'll be Autocool on Lord St.
I had them re-seal a compressor of mine about 8 years ago also. They're my go-to for parts and advice. Last time I wanted a compressor (for a different make) I was pleasantly floored at how "economical" it was for a genuine Sanden.

Turns out PAG just isn't that good a lubricant, and compressors "aren't made like they were", so I don't bother with seals or valves anymore. Just put a new one in before it grinds itself to dust and contaminates the whole system.

[haydent]

*update see later post LR020449 is for l322 not l320 despite same motor...

I contacted 2 Sanden resellers in australia, and they said the part number Sanden 8649E LR020449 (3.6L V8) is not in the country at all. So I order one from uk company online with a dryer too.

Local Natrad AC guy has no time to fit it, but says he can take the gas out and ok for me to drive it home, fit it all and bring it back for regas, which ill consider.

he said he'd usually do a TX valve depending on access, but ours seems to be behind the instrument cluster, so ill pass. I believe this is what lr call "Thermostatic Expansion Valve"

$814 aud inc DHL shipping

[DiscoJeffster]

I contacted 2 Sanden resellers in australia, and they said the part number Sanden 8649E LR020449 (3.6L V8) is not in the country at all. So I order one from uk company online with a dryer too.

Local Natrad AC guy has no time to fit it, but says he can take the gas out and ok for me to drive it home, fit it all and bring it back for regas, which ill consider.

he said he'd usually do a TX valve depending on access, but ours seems to be behind the instrument cluster, so ill pass. I believe this is what lr call "Thermostatic Expansion Valve"

$814 aud inc DHL shipping

Get a new condenser too. That’ll be easy enough to find locally. You should really flush the lines and evap core too else gunk might cause the new one to fail.

Also, you’ll need to get the oil quantity correct. Do you have rear AC? If so, you need to account for that as well.

[haydent]

Get a new condenser too. That’ll be easy enough to find locally. You should really flush the lines and evap core too else gunk might cause the new one to fail.

Also, you’ll need to get the oil quantity correct. Do you have rear AC? If so, you need to account for that as well.


no rear ac, yeah ive read the amount of oil in the new pump is not necessarily enough. ill ask to get a flush done after gas removal.

replace condenser though ? why ? (thats the radiator on the front.)

[DiscoJeffster]

no rear ac, yeah ive read the amount of oil in the new pump is not necessarily enough. ill ask to get a flush done after gas removal.

replace condenser though ? why ? (thats the radiator on the front.)

You can’t effectively flush them so it’s always a good idea to replace it. Pretty cheap insurance. Yes, the front.

[BradC]

no rear ac, yeah ive read the amount of oil in the new pump is not necessarily enough. ill ask to get a flush done after gas removal.

replace condenser though ? why ? (thats the radiator on the front.)

Parallel flow condensers have tiny passages and are almost impossible to flush adequately. The condenser is first cab off the rank past the compressor so as the compressor slowly grinds itself away a lot of the aluminium grunge gets caught in the condenser. If the condenser isn't replaced it can find its way back into the system and cause premature wear on the new compressor.

[haydent]

not sure if should cancel order and change it, would cost an extra $350 aud to get a condensor LR097939 , so not cheap insurance but still a benefit

[BradC]

not sure if should cancel order and change it, would cost an extra $350 aud to get a condensor LR097939 , so not cheap insurance but still a benefit

Not "cheap insurance", but if it prevents you from having to do another compressor then it's not particularly expensive in the scheme of things.

[PerthDisco]

As a DIY question can you fit your new compressor and evaporator. Hook it all up and drive to a AC shop to get it flushed and charged without ruining the new compressor? You’d have to have the belt on and compressor turning even with the system off.

[BradC]

As a DIY question can you fit your new compressor and evaporator. Hook it all up and drive to a AC shop to get it flushed and charged without ruining the new compressor? You’d have to have the belt on and compressor turning even with the system off.

On a D3? No. According to the wiring diagram the D4 has a clutch on the compressor (controlled from Relay R181 in the engine bay fuse box. Fuse 11E apparently) along with the variable valve.

[haydent]

well this is the reason i actually posted this. natrad tech says ok, and i tend to agree, as there is the clutch inside the pump that when the ac is off (or there is no gas pressure as there will be once removed) afaik disconnects the drive to the pump itself, this needs to be there to stop the pump destroying itself if you leak all your gas.

[BradC]

well this is the reason i actually posted this. natrad tech says ok, and i tend to agree, as there is the clutch inside the pump that when the ac is off (or there is no gas pressure as there will be once removed) afaik disconnects the drive to the pump itself, this needs to be there to stop the pump destroying itself if you leak all your gas.

There is no clutch inside the pump. If the pump doesn't have a clutch on the pulley, then it is always running even if at minimum displacement (~5%).

Edit: The LR020449 part number you quoted shows images of a Sanden compressor *with* an external clutch.

Edit2: It cross references to a Sanden PXV, which has an external clutch and internal displacement control. So the car has no control over the displacement, the compressor manages that internally based on the suction pressure. The car simply switches it on and off.

The oddities that are differing Land Rover engine configurations. Didn't realise yours is a V8. As you were...

[haydent]

LR020449 - COMPRESSOR ASSY | LR Parts (https://www.lrparts.net/lr020449.html)
thanks for your input, i thought it was displacement car controlled as well, as in iid tool it shows changing output for clutch status and ac compressor current, which im told the unit is wrong but that is the displacement reading. but ive never looked at it when not working, so maybe it just always is either 255 or 0, as an assumed displacement value rather than a measured one.

*update see later post LR020449 is for l322 not l320 despite same motor...

[haydent]

so whats to stop one without a clutch destroying itself if you run out or leak all your gas ?

[BradC]

LR020449 - COMPRESSOR ASSY | LR Parts (https://www.lrparts.net/lr020449.html)
thanks for your input, i thought it was displacement car controlled as well, as in iid tool it shows changing output for clutch status and ac compressor current, which im told the unit is wrong but that is the displacement reading. but ive never looked at it when not working, so maybe it just always is either 255 or 0, as an assumed displacement value rather than a measured one.

If it's displacement controlled there will be 2 connectors to the compressor. One for the displacement valve and one for the clutch. The Sanden PXE series does say it's "internal control variable displacement".

Swash Plate Type / PX series | Products | SANDEN (https://www.sanden.co.jp/english/products/car/compressor_px.html)

Just another "thing" to get on top of.

For the record, what precisely is it you are driving and with what engine configuration (3.6V8?). I can't find that on any of the Disco wiring diagrams I have here, which is what confused me.

[haydent]

*update see later post LR020449 is for l322 not l320 despite same motor...
i did post here D4 A/C Compressor issue (https://www.aulro.com/afvb/l319-discovery-3-and-4-a/268239-d4-c-compressor-issue-post3171291.html#post3171291)
l320 2010 tdv8
LR020449 sanden pxv16 8649e
181999
181998

[PerthDisco]

On a D3? No. According to the wiring diagram the D4 has a clutch on the compressor (controlled from Relay R181 in the engine bay fuse box. Fuse 11E apparently) along with the variable valve.

So you’d have to flatbed it to the AC shop?

[haydent]

so whats to stop one without a clutch destroying itself if you run out or leak all your gas ?
[bighmmm]

[josh.huber]

[bighmmm]

The ones without a clutch will literally just die and take the belt with them.. Same as a dead water pump etc

[josh.huber]

So you’d have to flatbed it to the AC shop?

Without an external clutch, yes, or use a mobile guy

[josh.huber]

Definately get a condenser, especially if your not equipped correctly to flush at home. Get them to jam at least 100ml of extra oil in it.

Buy genuine O rings for everything

[gavinwibrow]

Definately get a condenser, especially if your not equipped correctly to flush at home. Get them to jam at least 100ml of extra oil in it.

Buy genuine O rings for everything



Sounds logical, but what is the rationale for the extra oil please?

[LuckyLes]

The compressor pictured has a clutch which is powered on when you turn on the a/c. The variable control valve varies the capacity of the compressor to keep the correct flow of refrigerant required. The clutch does not cycle on and off as in older thermostatically controlled systems.
If you don't understand how the system works why would you try and fix it yourself.
The first thing to determine is WHY did the compressor fail, or is it just a failed valve. If a complete compressor failure then a new TX valve and drier and condenser is called for.
If the system was low on refrigerant, where did it go. Modern systems do not leak from compressor seals or hoses as did older ones. Did the system suddenly stop cooling, or was it not performing properly for some time.
These are all questions that need to be answered before spending big bucks on parts that may or may not be the cause of the failure.
Consult an expert.
LuckyLes

[josh.huber]

Sounds logical, but what is the rationale for the extra oil please?

Oil coats the inside of all parts. So by changing the condenser, your removing about 40ml of oil, the drier about the same, the compressor will come short too.

I can't remember the number, but I "THINK" the compressor came with 70ml and the system is 240ml.

The quantities are in an old post of mine, but I always add oil, a bit extra is allot better than not enough. To much oil decreases cooling efficiency, not enough kills compressors. I've never noticed a cooling deficiency per say, but the theory is solid.

[scarry]

Why not pour the oil out of the old compressor and measure it?
That will give an accurate measurement of oil the new compressor will need.

Same for condenser and drier,but maybe more difficult,possibly have to leave them draining over night.

The evaporator will also have oil in it,and in some cases can by oil logged,particularly when the system has been operating at low pressures,such as when low on refrigerant,but a huge job to get it out and drain.

[josh.huber]

Why not pour the oil out of the old compressor and measure it?
That will give an accurate measurement of oil the new compressor will need.

Same for condenser and drier,but maybe more difficult,possibly have to leave them draining over night.

The evaporator will also have oil in it,and in some cases can by oil logged,particularly when the system has been operating at low pressures,such as when low on refrigerant,but a huge job to get it out and drain.

As for draining the compressor, yes 100%. That's how I worked out they needed so much more oil.. You'll never drain a condenser or hose as it's coated the inside. There are charts for how much oil to add per metre of hose etc.

I normally drain the compressor and change the oil to a synthetic oil as it's non hygroscopic then flush the system. Add the appropriate amounts where I can.

[haydent]

The ones without a clutch will literally just die and take the belt with them.. Same as a dead water pump etc

the clutchless ones have a sacrificial pulley to pump connection so in theory if it seizes that gives way and the belt can keep going.

I was able to cancel my order and am getting a condenser on everyones recommendation and also for that fact that i have to pull the old one out to get to the dryer

Mine had not leaked, gas ok, for some time would take 10mins to produce cold air, and then sometimes 30 mins, and now not at all. Only making hot air if running, so the pump must by circulating and getting power.

It could be valve inside pump, but not sure if even replaceable on internal controlled, consensus from my other posts in threads seems to be safer to just replace pump for the confined work involved which is the biggest issue.

LR gives these recommendations re oil and gas, apart from the gas capacity, the oil recommendations are the same for the 2.7D and V8 petrols in my manual.

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[haydent]

Plot twist, (i should have looked at the one on the car sooner) thats not the compressor I have/need (currently cancelling order, again...)

LR020449 (sanden) with clutch is in l322 (same engine), and for my l320 (and this is confirmed by lr centre uk, and my eyes) that i need LR018405 (denso) (which is nearly twice the price)

And as it turns out is an externally controlled displacement pump with no clutch, so im back at square one.

And it turns out mine has green oil over it so it so must be leaking, I can only hope the natrad tech was right that its gas level was ok, and its not actually empty and slowly destroying itself and the rest of the system.

I believe this is the one

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DENSO 7SEU17C dcp14019

[haydent]

So pulled the trigger on order #3, compressor, condenser and orings, $1500aud delivered from lrparts.net (uk) ,

price makes eyes water, especially when you see the same line of compressor (just with different angle pipe connection) stocked and sold online in australia for Mercedes van only $500aud,

but you tell yourself, its ok, at least not paying genuine prices listed at over $2k aud just for the compressor.

[BradC]

Potentially silly question, but did you get a quote from a proper vehicle AC specialist (not a chain)? Only brought it up because every time I've done that they've been able to get excellent pricing. Frankly even if they were 15% more expensive, I'd pay that for local support and warranty.

[haydent]

Potentially silly question, but did you get a quote from a proper vehicle AC specialist (not a chain)? Only brought it up because every time I've done that they've been able to get excellent pricing. Frankly even if they were 15% more expensive, I'd pay that for local support and warranty.

I agree, and still may get a tech to install with my imported parts, but i rang several denso resellers and they just dont stock that part in australia....

[LuckyLes]

So, if you get a "tech" to install the parts you source, who is going to cover the warranty? He will cover his work, but if a part fails he won,t be covering the labour costs to replace it, or the reclaim and recharging of refrigerant.
Just my two bobs worth.
LuckyLes

[haydent]

So, if you get a "tech" to install the parts you source, who is going to cover the warranty? He will cover his work, but if a part fails he won,t be covering the labour costs to replace it, or the reclaim and recharging of refrigerant.
Just my two bobs worth.
LuckyLes

Ive been hit up before by mechanics for labour on failed parts supplied/fitted by them/their suppliers so no guarantee

[LuckyLes]

Ive been hit up before by mechanics for labour on failed parts supplied/fitted by them/their suppliers so no guarantee
If they supplied the part and it failed it is their duty to warrant the complete replacement, that is if it is new parts they supplied and not reconditioned or second hand ones.

[haydent]

It was reconditioned, but by ZF...

[scarry]

If they supplied the part and it failed it is their duty to warrant the complete replacement, that is if it is new parts they supplied and not reconditioned or second hand ones.

Not always,most warranties are parts only,possibly with freight if applicable.

Some may pay a portion of labour as a good will gesture,but many will not.

[haydent]

regardless, half the users wouldnt be here if it was always the best option to have all work done for you

[LuckyLes]

regardless, half the users wouldnt be here if it was always the best option to have all work done for you

I understand that, but buying expensive bits and throwing them at the car on what is no more than a guess is not all that smart, and most times ends up more expensive.
As an example, most Denso compressors, the same compressor body is used for a lot of vehicles, with the only difference being the clutch/pulley assembly, the ports for the hose connections, and possibly the rear plate. All of these bits are removable and can be replaced with parts from the old compressor, a bit like putting a short motor in the car. There is a certain amount of skill in doing these things that comes with experience, and a good product knowledge.
This is what people go to a specialist for. Just like we use an Indie to do or advise us on the mechanical side. A properly trained automotive a/c tech knows this stuff inside out. Not your average mobile regas guy that has no more training or product knowledge, than your average lawn mower man. (Not denigrating lawn mower men by the way)

[LuckyLes]

It was reconditioned, but by ZF...

An auto transmission. Did the mechanic send it to them or did you. If you took it to him, and he advised sending it to ZF, removed it, sent it down, and then refitted it, then the whole job is his, and he should cover it. What ZF do is between him and them.

[josh.huber]

I understand that, but buying expensive bits and throwing them at the car on what is no more than a guess is not all that smart, and most times ends up more expensive.
As an example, most Denso compressors, the same compressor body is used for a lot of vehicles, with the only difference being the clutch/pulley assembly, the ports for the hose connections, and possibly the rear plate. All of these bits are removable and can be replaced with parts from the old compressor, a bit like putting a short motor in the car. There is a certain amount of skill in doing these things that comes with experience, and a good product knowledge.
This is what people go to a specialist for. Just like we use an Indie to do or advise us on the mechanical side. A properly trained automotive a/c tech knows this stuff inside out. Not your average mobile regas guy that has no more training or product knowledge, than your average lawn mower man. (Not denigrating lawn mower men by the way)

While your point is valid, no one in today's age is going to open a brand new compressor, void the warranty to swap a port plate, the seal kit and time makes it a bad idea, it works only if no others are available. This is common place on sanden SD7H15 compressors.

Speciality comes in diagnosis not modifying parts. In this case, he has sought the advice of others, the compressor is dead, he bought a condenser and drier.

The best AC guy I know operates out of a van

[LuckyLes]

While your point is valid, no one in today's age is going to open a brand new compressor, void the warranty to swap a port plate, the seal kit and time makes it a bad idea, it works only if no others are available. This is common place on sanden SD7H15 compressors.

Speciality comes in diagnosis not modifying parts. In this case, he has sought the advice of others, the compressor is dead, he bought a condenser and drier.

The best AC guy I know operates out of a van

Diagnosis is the start of the process. He has been told that the compressor is not pumping, but no one has said definitely why.
Sanden SD7H15 compressors do not have a control valve, they are operated by a thermostatically controlled clutch.
He doesn't know that the compressor is dead, he just knows that it doesn't work.
He stated that it was not the sanden but a Denso compressor on his vehicle. The scenario I brought up is something that I used to do on a regular basis. My shop was an authorised Denso repair centre, we had the training and the experience and our clients came to us because we were able to offer a repair that was not able to be offered by many shops or mobile operators. These people came to us when they weren't able to source the parts. This was before the internet made the market a worldwide source.
I started off working from a van, and over a period of well over 20 years, grew my experience and knowledge to where I was able to do that.
What I am saying is that just because there in not a compressor with the correct part number on it doesn't mean that it can't be built from parts, at a reasonable cost.
He stated that the same compressor was on other Euro cars, but with differing ports, at a reasonable cost.
I have recommended an a/c specialist in Brisbane that has the ability and expertise to do just that.

[haydent]

I actually posted earlier that Id noticed the mercedes compressor was half the price and just had different pipe/port angles, so sure in an ideal world it would be nice to do as you suggest (assuming the tech gave full warranty), but im 400km from the nearest capital city, and just the mention of range rover to a mechanic around here scares them off (and who are all booked out for weeks).

Also I posted earlier, that the denso has green all under it from the front, so i know its leaking, i also know its pumping as when turned on you get hot air rather than ambient temp air, (i know its not a air mixer problem, as have gap tool) so it would seem its moving engine heated gas/fluid around the pipes, which the natrad guy did test is still there, but not making any pressure difference between H and L

[LuckyLes]

[QUOTE=haydent;3171796]I actually posted earlier that Id noticed the mercedes compressor was half the price and just had different pipe/port angles, so sure in an ideal world it would be nice to do as you suggest (assuming the tech gave full warranty), but im 400km from the nearest capital city, and just the mention of range rover to a mechanic around here scares them off (and who are all booked out for weeks).

Also I posted earlier, that the denso has green all under it from the front, so i know its leaking, i also know its pumping as when turned on you get hot air rather than ambient temp air, (i know its not a air mixer problem, as have gap tool) so it would seem its moving engine heated gas/fluid around the pipes, which the natrad guy did test is still there, but not making any pressure difference between H and L[/QUOTE

Your car, your money, do as you want. If your time is worth more to you well then that's fine, and I have no problem with that. I offered a suggestion when advice was sought that's all.
I'll keep my thoughts to myself.

[haydent]

I'll keep my thoughts to myself. dont, because I appreciate everyone's input


Plot twist, taking the fan and belt off today to see if possible to fit a shorter belt to bypass the pump and I worked out the sacrificial 'clutch' is actually broken ! Not knowing what it was earlier, id looked down the front of the engine and seen the front connector mechanism at an angle, and put my hand down there and it just came off.

At the time I thought it was just a vibration damper due to all the rubber bits, but being broken it means the pulley just free wheels. This is meant to break if the pump seizes to save the belt, and it would have been a 5 minute diagnosis to look at the front of the pump when engine running and see the center bolt not turning....

So I took the pulley off and it turns out the pump isnt seized, so either it momentarily seized or it broke from fatigue due to being alloy and all the pump force having to be transferred through it....

This means my pump might actually be fine (apart from the leak) and still pump ok if i replace the front plate for like $25 ! And I wont have to pull the car apart, though my order from the UK just shipped.

Also something interesting, one could actually remove this hub part on a working pump so it would free wheel between home and the gas technician, and then replace once gassed.

Here is a video that shows difference between broken and not, similar design but not same pump

BROKEN ac compressor “sheer hub” drive plate clutchless denso (variable displacement) - YouTube (https://www.youtube.com/watch?v=J-XonHhFtho)

Here is a photo of the same looking part I pulled off my car, with the broken shear points marked.

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what it looks like from front

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And the tool you would want to get the hub plate on/off without risk of breaking the clutch, though teh LR manual doesnt mention one, I would use one.

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Though maybe they allude to it but not show it

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So Ill try getting another hub plate domestically from a wrecker or denso supplier, otherwise china, as id be happy to put the new parts in the shed for now if I can get away with it for now at least...

[haydent]

** Update, the pump does seize intermittently I can spin it like 4-10 times, very smooth, no problem, and then it randomly just locks up in that direction. I also tried getting the broken hub nut off (yes I know its reverse thread like the fan), but it was seized so bad i rounded and bent the baby 7mm head it has on the end of the shaft, so that would make the pump irreparable anyway. Im guessing when the pump seized and broke the hub it torqued the nut up crazy tight...

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[LuckyLes]

So those that had looked at it for you weren't on the ball. Other than the one who said compressor is cactus but for the wrong reason. It wasn't pumping hot gas around at all. It wasn't pumping period.

[haydent]

So those that had looked at it for you weren't on the ball. Other than the one who said compressor is cactus but for the wrong reason. It wasn't pumping hot gas around at all. It wasn't pumping period.

Only person I had look at it was the natrad guy who didnt look at where the pump was, super busy, just tested the gas pressure with the AC off and on, enough to say there was enough gas in it, and that the pump wasnt kicking in as no higher pressure on the high side. I could see this too with the gap tool, as it gives a pressure readout from the H side. He thought it could have been electrical too, but I could see it didnt seem that way from gap readings and lack of errors, so he agreed it could be the pump but was hesitant to say it to me right away.


It was just my theory that it was pumping engine heated liquid around as an explanation for the hot air, but now that cant be, as pump not rotating. But what I think might have been happening instead is just thermosiphon (due to the evap being higher than the pump), being turned on and off by the control valve in the pump which is likely still working, I dont think theres any other electric control of the ac system as with AC off, fan vent air still goes through the cabin ac radiator evaporator.


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[haydent]

also just to keep this a little relevant to the topic title, (i will move back to the l320 forum in a bit) it seems the d4's / 2.7 have a very similar looking denso and that is an engine option in my l320 manual and the hub instructions look identical, though the principles ive been going over would apply to the sanden one too LR013841 - Air Con Compressor for Discovery 4 2.7 TDV6 | LR Parts (https://www.lrparts.net/lr013841-air-conditioning-compressor-for-discovery-4-with-2-7-tdv6-engine-doesn-t-fit-discovery-3.html)

[josh.huber]

Change all the parts your ordered, get them to add heaps of oil.. Enjoy life with windows up.

If it was mine. If get a mobile guy to quickly flush the TX and evap, then come back and push the gas in.

Air con is never cheap, gas and parts are getting more expensive every day, so is licensing, training and staying up to date with everything..

[haydent]

Change all the parts your ordered, get them to add heaps of oil.. Enjoy life with windows up.

If it was mine. If get a mobile guy to quickly flush the TX and evap, then come back and push the gas in.

Air con is never cheap, gas and parts are getting more expensive every day, so is licensing, training and staying up to date with everything..

I live 40km from the nearest town, but will be enquiring to availability and costs of mobile mechanic. otherwise ill just drive in with guard inner trim removed, get gas removed and get flushed if accessible, drive home change pump with clutch hub removed and condenser, drive back in get gas, drive home put hub on.

[BradC]

drive back in get gas, drive home put hub on.

Put the hub on before you let the A/C guy gas it up otherwise there's no way to test it.
If he's any good, he's going to want at least a standing leak test, so budget some extra time. It's not just a case of "git 'er done".

[haydent]

Put the hub on before you let the A/C guy gas it up otherwise there's no way to test it.
If he's any good, he's going to want at least a standing leak test, so budget some extra time. It's not just a case of "git 'er done".

I will if i can, access and permissions pending, as had to drain some of the coolant, remove 2 radiator hoses and 2 intercooler hoses , and fan to get to the compressor front from top. Maybe I will be able to do it through the side wheel arch once I get that inner panel off

[haydent]

I asked a local goodyear mechanic when getting some new tyres to look up a labour estimate on ac pump/condenser replacement, as they do mechanical and hychill ac as well not just tyres.

He couldnt find it in his software so rang landrover, who said I would require a full system replacement due to pump failure including tx valve and evaporator. Potentially involving body off, and it would take one of their trained/experienced technicians 26 hours labour...

Im hoping seems my pump doesnt feel like its ground itself to a seized halt that it wont have filled the system beyond the condenser with metal. Once I get it open ill start by inspecting the hose leaving the condenser.

Also Ive read online and the mechanic today confirmed you cant flush through a tx valve, so to flush completely you would have to take that out...

[DiscoJeffster]

Replacing the aircon evaporator is *slightly* involved...like a LOT involved ? | By JAS LR - Land Rover Specialist (https://fb.watch/h7HPKEcg6T/)

How to get to the evaporator [emoji15][emoji15][emoji15][emoji15][emoji15]

[PerthDisco]

Shanegtr on Shane Shed on YouTube has changed his AC compressor!

Wow - evaporator! If you had nothing to do for a month and a nice shed that would be quite an interesting job.

Once you get the seats out working in that area gets a lot easier instantaneously.

[scarry]

I asked a local goodyear mechanic when getting some new tyres to look up a labour estimate on ac pump/condenser replacement, as they do mechanical and hychill ac as well not just tyres.

He couldnt find it in his software so rang landrover, who said I would require a full system replacement due to pump failure including tx valve and evaporator. Potentially involving body off, and it would take one of their trained/experienced technicians 26 hours labour...

Im hoping seems my pump doesnt feel like its ground itself to a seized halt that it wont have filled the system beyond the condenser with metal. Once I get it open ill start by inspecting the hose leaving the condenser.

Also Ive read online and the mechanic today confirmed you cant flush through a tx valve, so to flush completely you would have to take that out...

Land Rover again bending over it's customers,unfortunately also giving the brand a bad name.

The Drier will catch most if not all the bits and pieces,and there will be some in the condenser.
We use suction line driers in commercial refrigeration,one fitted to an Auto AC system would probably be difficult,even temporary,but it would definitely help clean up the system,and stop any rubbish getting into the new compressor.

Last resort,hot water poured over a TX valve and the power element bulb will get it to open,so the system can be flushed,but if the TX is not accessible,this will be impossible.Taking the valve out,as said, is preferable.

[DiscoJeffster]

Sounds like it’s simplest to risk the Evap and tx and just change the compressor, dryer and condenser and cross your fingers

[josh.huber]

Sounds like it’s simplest to risk the Evap and tx and just change the compressor, dryer and condenser and cross your fingers

It's not really a risk, it's a series circuit. Compressor, condenser, (long path little holes) drier, (filter), then TX valve.

You shouldn't flush through a tx valve, but I have a 1000 times.. I always get nervous but still do it.. All you ever get out is oil. If be more nervous to not flush..

[haydent]

Update, I was changing the tyre size with gap, and checked the errors, now there is new one saying the AC system pressure is too low. I checked the reading and it is basically nothing, so it would seem everything has leaked out anyway, so this will save me getting the system drained.

Interesting thing though is that this error does not raise any messages/warnings on the dash, so you could be driving around with no gas and not know, while the pump is still turning, maybe it doesnt matter, maybe it does, no clutch, but maybe the oil stays in the pump...



Replacing the aircon evaporator is *slightly* involved...like a LOT involved ? | By JAS LR - Land Rover Specialist (https://fb.watch/h7HPKEcg6T/)

How to get to the evaporator [emoji15][emoji15][emoji15][emoji15][emoji15]

worse than I thought, not going to be doing that.


Shanegtr on Shane Shed on YouTube has changed his AC compressor!

turns out ive seen that video, but will be watching it aga'n


The Drier will catch most if not all the bits and pieces,and there will be some in the condenser.

Looking at the flow, it seems it goes from the pump to the bottom of the condenser, and then exits from the top, so you'd expect heavy metallic bit to stay in the bottom.


Sounds like it’s simplest to risk the Evap and tx and just change the compressor, dryer and condenser and cross your fingers

In hindsight i think I would have instead looked into getting a $2-300 7SEU17C core for a different car, and swapping the bits over if possible to do it cheaper in case something goes wrong.

[shanegtr]

Interesting thing though is that this error does not raise any messages/warnings on the dash, so you could be driving around with no gas and not know, while the pump is still turning, maybe it doesnt matter, maybe it does, no clutch, but maybe the oil stays in the pump...


For what its worth (and I'll be surprised if someone doesn't have a go) but I run around for 5 months with my new compressor in before I recently got it regassed. I had every intention of getting it done straight after installing the compressor, however life had other ideas for me and it got put on the back burner until the weather started warming up[bighmmm]. The D3 really holds the heat in with no working A/C

[haydent]

For what its worth (and I'll be surprised if someone doesn't have a go) but I run around for 5 months with my new compressor in before I recently got it regassed. I had every intention of getting it done straight after installing the compressor, however life had other ideas for me and it got put on the back burner until the weather started warming up[bighmmm]. The D3 really holds the heat in with no working A/C

so what model pump is it ?

we have sheep skin covered seats and all the car sound proofing, also a bit much with windows down full on highway ... we were cooking inside and outside temp only 24 deg, glad it not a hot summer (yet at least)

[shanegtr]

its on an 05 D3. Can't recall model, but the LR part number is LR014064

[haydent]

its on an 05 D3. Can't recall model, but the LR part number is LR014064

Discovery 3 2.7TDV6 AC compressor change - YouTube (https://www.youtube.com/watch?v=BRWti8nwoAA&lc=UgzoZFawSMwtW8Oj14Z4AaABAg.9jCUfoY8Eu59jDJ5ywNT 3l)

lol, we are running parallel conversations ! interesting to know you ran an external displacement controlled pump with no gas for a bit

[haydent]

So Im a bit over half way through repair in just one day, have replaced the condenser and got the old pump out.

Im posting all my photos and notes in this thread: https://www.aulro.com/afvb/l320-range-rover-sport/293631-c-compressor-condenser-change-pics-notes.html#post3176031

I have some questions about oil, I will call local AC guy when open next to discuss and likely get some more oil.

I drained the old pump and only got 40ml oil (though some was spilt, maybe 5-10ml) but it seems plenty as likely leaked with gas.

There are metal flecks in the oil from pump, but no oil traces seem to be exiting the old condenser, so hopefully no metal parts, pump installation manual says if metal in oil replace whole system...

I will flush the line between pump and condenser and inspect tomorrow.

Installation manual with pump says not to add oil to direct to pump, only else where.

The pump comes with oil, manual says 1.4 fl (41ml) oz for condenser replacement.

Manual says total system capacity 4.5 fl oz (133ml) , maybe I should check how much is in the pump ?

182694

182693

182691

182692

[scarry]

What do you guys use to flush the system?

[josh.huber]

So Im a bit over half way through repair in just one day, have replaced the condenser and got the old pump out.

Im posting all my photos and notes in this thread: (coming soon)

I have some questions about oil, I will call local AC guy when open next to discuss and likely get some more oil.

I drained the old pump and only got 40ml oil (though some was spilt, maybe 5-10ml) but it seems plenty as likely leaked with gas.

There are metal dust in the oil from pump, but no oil traces seem to be exiting the old condenser, so hopefully no metal parts, pump installation manual says if metal in oil replace whole system...

I will flush the line between pump and condenser and inspect tomorrow.

Installation manual with pump says not to add oil to direct to pump, only else where.

The pump comes with oil, manual says 1.4 fl (41ml) oz for condenser replacement.

Manual says total system capacity 4.5 fl oz (133ml) , maybe I should check how much is in the pump ?

182694

182693

182691

182692

That oil has heaps of dye in it, there is a bolt in the centre of the compressor, add oil in there, basically the sump, as for the rest of the oil..pour into the inlet off each item if you want.

What do you want to know about the oil?

[josh.huber]

What do you guys use to flush the system?

If it's filthy, brake clean first then AC flush from the wholesalers, if it's not too bad. Just the flush straight up.

Use with a compressor and the tank type flushing gun

[haydent]

Im assuming the green dye means its been refilled since new, possibly it already had a slow leak before i bought it, or its just normal leakage in 10 year car. Its probably been low on oil considering small amount I got out so may have lead to failure. I wonder if AC guy would add oil during regass or not...

So Im thinking if I do (I may not) attempt a diy flush past the tx (still installed) with new pump and condenser not in the loop, I would not be abel to connect the pump until I get it to the AC guy to put a vac on it to evap the solvent i use, ive read about turps/acetone/metho with mixed opinions. So then hook the pump up once at AC place and had vac pulled, as dont want any solvents getting into the pump/pump oil. Ill ask the AC guy what he thinks and if he can do one.

As for oil do I pour out what oil is in the pump to measure it, and then add it back in, plus the difference to make up 4.5 fl oz (133ml), I will like get it added in the H or L valve, this way I can put it all together, and drive into town, get extra oil and gas added.

Here is the manual that came with the pump, interesting to note section on "Run in procedure", and instruction to "Never add oil directly into the compressor"

182695182698182697

[haydent]

Just got off phone to local AC tech, he said impossible to flush past TX valve so I dont think ill bother with flushing.
He also didnt seem to think I needed to add any more oil to the pump. (I think Ill still measure it just to know, in case I decide post install (today) I decide to add more, (which his machine can do during gassing).
He also didnt think there was any problem driving it without the gas, and considering shane said he drove his for 5 months with no gas, its likely fine. I was thinking that seems the pump has oil in it, it should be fine and any that gets flicked out would just run back in as lowest point in system. This way I can just put it all back together and drive in ready to be gassed tomorrow.

[LuckyLes]

Looking at the debris in that oil, I would at least be changing the TX valve. You can't successfully flush the system with the valve in place.

[scarry]

If it's filthy, brake clean first then AC flush from the wholesalers, if it's not too bad. Just the flush straight up.

Use with a compressor and the tank type flushing gun

We use shellite.
Easiest way is to suck a few litres into an old 20kg refrigerant bottle,pump up with 200 PSI of nitrogen,if it doesn’t have a liquid valve,tip it upside down and away you go.
Some wholesalers have a little vessel that has a schrader valve on each end and a screw cap,can be used as well,but generally to small for most of our systems.
We also generally cut the system up,and take out the expansion device,did a 30KW AC unit last week,compressor had smashed up,the whole system was filthy.We always fit a new liquid and pipe in a suction drier.Return after a few days,change compressor oil,and depending,replace driers again.

[scarry]

Looking at the debris in that oil, I would at least be changing the TX valve. You can't successfully flush the system with the valve in place.

I would try first,we have done it on many occasions,if we have to.

[LuckyLes]

OP has posted again while I was replying and has spoken to his a/c tech who advised him much the same. The difference between an auto car system and a commercial system is accessibility of the components. If he gets to the recharge point and finds that the TX is blocked or jammed, basically he has to start again. Also he is risking passing fine bits of metal through the new compressor that he has paid big bucks for.

[haydent]

So I just put the compressor on the pipe to the condenser, and air comes out the other larger pipe from the cabin, there is restriction that would prevent a high flow flush, but enough to know the tx isnt blocked completely, and maybe enough to do a basic flush...

This is why im not too interested in TX access: (if i had my time again, id have bought 2-300 dollar 7SEU17 pump used/aliexpress in case it does die from contamination)

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[LuckyLes]

You're doing the job and asking for advice. Advice has been given from the start that you haven't taken on board. It's your money, do it whatever way you reckon will fix it.
Done correctly it should last another 10 - 15 years, partially done it may last 10 or more years, or it may last 10 or more days.

[haydent]

You're doing the job and asking for advice. Advice has been given from the start that you haven't taken on board. It's your money, do it whatever way you reckon will fix it.
Done correctly it should last another 10 - 15 years, partially done it may last 10 or more years, or it may last 10 or more days.

I know ultimately its a decision ive got to make myself and bear the result. I have actually taken some of the advice given from the start, such as replacing the condenser along with the drier.

If the advice you are thinking of is to just leave it to the 'professionals', cant do that no one around here wants to touch it.

Its not that im not capable of taking the dash apart to get to the TX its more im looking to avoid it if possible. Why do I think I can get away with that ?

Well if you go by the book, as maybe you are suggesting id be tearing the whole interior out to replace the evap too and all the pipes, but thats not going to happen (without trying a pump/condenser swap first).

I hope/suspect that most of the metal if any that got out of the pump will have settled in the bottom of the condenser I swapped.

I also dont think a low pressure flush (with tx valve in place) will clear much other than oil the solvent can dissolve, and like i said, i dont think even a flush without the tx would get rid of all metal in the bottom of the evap (if any) thus the instruction by denso, landrover and triumph rover spares to replace the whole system.

I havent seen any traces of metal at the condenser connections or pump return connection.

Im just as much seeking opinions as much as documenting my process and situation for others, even if it does go right or wrong.

182708

[BradC]

Its probably been low on oil considering small amount I got out so may have lead to failure.

If it has been running with low refrigerant the missing oil is probably in the evaporator, which is another reason it really needs to be flushed.

[haydent]

I checked the amount of oil in the pump 120ml (clear oil) then saw the label on the new pump actually lists it, 130cc (130ml) might get about 10-20ml and dye added with gas.

[haydent]

If it has been running with low refrigerant the missing oil is probably in the evaporator, which is another reason it really needs to be flushed.

the tech said the gas amount was ok when he tested it when it wasnt working initially (due to siezed and broken pulley)

why would it be in the evaporator and not the condenser ? because as the liquid evaporates it leaves the oil behind ?

[BradC]

the tech said the gas amount was ok when he tested it when it wasnt working initially (due to siezed and broken pulley)

The only way to do that is to pull the gas out and weigh it. Did the Natrad guy do that?


why would it be in the evaporator and not the condenser ? because as the liquid evaporates it leaves the oil behind ?

Bang on. In a fully charged system there is enough vigorous boiling in the evap to spit the oil out the suction line, but as the refrigerant level drops that reduces until the evap gets oil logged, the compressor is starved of oil and it lunches itself.

It's why I always bang on about the "periodic regas". All systems leak. Even fully brazed hermetic systems leak. It's the leak rate that differs. These systems have a rotating seal on the compressor and elastomer seals on every joint. They *all* leak.

[haydent]

The only way to do that is to pull the gas out and weigh it. Did the Natrad guy do that?



I dont think so, could you not tell by just testing the idle system pressure ? Thats how a diving tank measures time left...




Bang on. In a fully charged system there is enough vigorous boiling in the evap to spit the oil out the suction line, but as the refrigerant level drops that reduces until the evap gets oil logged, the compressor is starved of oil and it lunches itself.



very likely, still thinking about that dash, maybe, maybe not. might put the pump back in (lines disconnected) while i think.

[DiscoJeffster]

I dont think so, could you not tell by just testing the idle system pressure ? Thats how a diving tank measures time left...




very likely, still thinking about that dash, maybe, maybe not. might put the pump back in (lines disconnected) while i think.

The forty hours to get that Evap out to replace the TX. No one would ever do this unless the Evap sprung a leak, right or wrong. That video I posted earlier shows the complete process.

[BradC]

I dont think so, could you not tell by just testing the idle system pressure ? Thats how a diving tank measures time left...

A diving tank stores compressed air. A refrigeration system stores refrigerant. They are not the same. At all times there is supposed to be liquid refrigerant in the system. Whether there is 1ml or 100L the pressure will be the same at the same temperature. Completely, totally and utterly different. You can not tell how much refrigerant is in a system by measuring the static pressure.

Can you tell how much gas is left in your 9KG gas bottle by measuring the pressure? No. Same reason.

[haydent]

The forty hours to get that Evap out to replace the TX. No one would ever do this unless the Evap sprung a leak, right or wrong. That video I posted earlier shows the complete process.
That was a good (but scary) video thanks. Im definately not contemplating that, just maybe a dash only to get to the tx.


A diving tank stores compressed air. A refrigeration system stores refrigerant. They are not the same. At all times there is supposed to be liquid refrigerant in the system. Whether there is 1ml or 100L the pressure will be the same at the same temperature. Completely, totally and utterly different. You can not tell how much refrigerant is in a system by measuring the static pressure.

Can you tell how much gas is left in your 9KG gas bottle by measuring the pressure? No. Same reason.

Well you can got a rough idea, I have pressure gauges for my gas bottles that have dials. I had a google and found this Why Can’t You Just Measure Pressures to Check a Refrigerant Charge? (https://www.acservicetech.com/post/why-can-t-you-just-measure-pressures-to-check-a-refrigerant-charge) so maybe he did it that way. I will ask him tommorow.

[BradC]

Well you can got a rough idea, I have pressure gauges for my gas bottles that have dials. I had a google and found this Why Can’t You Just Measure Pressures to Check a Refrigerant Charge? (https://www.acservicetech.com/post/why-can-t-you-just-measure-pressures-to-check-a-refrigerant-charge) so maybe he did it that way. I will ask him tommorow.

No you can't. You can get "gas or no gas". r134a at 25C is 1.206kg/L. The system holds ~600g. That's ~497ml. Whether it's that, or there's 1ml left the pressure will be the same.

He'd be a bloody good tech if he can do a superheat or subcooling measurement on a system with a lunched compressor.

[gavinwibrow]

It's why I always bang on about the "periodic regas". All systems leak. Even fully brazed hermetic systems leak. It's the leak rate that differs. These systems have a rotating seal on the compressor and elastomer seals on every joint. They *all* leak.


Maybe I've missed it but can you provide a bit more detail on periodic regas please (timelines etc)? I've often wondered why this is not a regular maintenance item, particularly given the problems/costs with total replacement/s.

[RANDLOVER]

https://www.aulro.com/afvb/images/misc/quote_icon.png Originally Posted by BradC https://www.aulro.com/afvb/images/buttons/viewpost-right.png (https://www.aulro.com/afvb/l319-discovery-3-and-4-a/268239-d4-c-compressor-issue-post3175880.html#post3175880)
It's why I always bang on about the "periodic regas". All systems leak. Even fully brazed hermetic systems leak. It's the leak rate that differs. These systems have a rotating seal on the compressor and elastomer seals on every joint. They *all* leak.






Maybe I've missed it but can you provide a bit more detail on periodic regas please (timelines etc)? I've often wondered why this is not a regular maintenance item, particularly given the problems/costs with total replacement/s.

I agree everything leaks, similar to Dr House's motto of "everybody lies" House (TV series) - Wikipedia (https://en.wikipedia.org/wiki/House_(TV_series)). Not sure on timelines but as soon as mine had a few of struggling to cool episodes I got my a/c gas topped up, following advice on this forum about the gas carrying oil around the system, basically they vacuum it out, weigh it, top it up and re-insert it in the system. Mine was missing quite a bit, and is noticeably colder now, can actually cause pain in my hands if the vents are directed at them.

Older shaft seals were notorious for leaking in winter when the a/c wasn't used, so manufacturers came up with all sorts of ideas to run the units, on timers, when reverse was engaged, etc.

[scarry]

The difference between an auto car system and a commercial system is accessibility of the components. If he gets to the recharge point and finds that the TX is blocked or jammed, basically he has to start again.

Exactly,who wants to pull it out if they don’t have to.

That is why I would give it a crack,that is flush with the valve in place.Do it from as close to the inlet of the valve as possible,to minimise the rubbish that goes into it.Any rubbish downstream of the drier is going to go into it anyway,once the system is operational.

As said,we have done it before on systems with TX and other types of expansion valves and had success.
Access to some of the expansion devices on systems we work on is also extremely difficult.
Takes a bit of time,and higher pressure.
Using shellite,as we do,once liquid shellite comes out the suction,clean,it is just about done.

Still better than not having a go.
Anyway each to their own.

[scarry]

If it has been running with low refrigerant the missing oil is probably in the evaporator, which is another reason it really needs to be flushed.

That is exactly what happened to that 30 KW AC system we sorted last week.We flushed 4.5L of black oil out of the evap.
Low on refrigerant,low pressure switch not working,etc,etc.

[haydent]

Exactly,who wants to pull it out if they don’t have to.

That is why I would give it a crack,that is flush with the valve in place.Do it from as close to the inlet of the valve as possible,to minimise the rubbish that goes into it.Any rubbish downstream of the drier is going to go into it anyway,once the system is operational.

As said,we have done it before on systems with TX and other types of expansion valves and had success.
Access to some of the expansion devices on systems we work on is also extremely difficult.
Takes a bit of time,and higher pressure.
Using shellite,as we do,once liquid shellite comes out the suction,clean,it is just about done.

Still better than not having a go.
Anyway each to their own.

yes im considering this, diy flush through the valve in the normal direction

edit, actually theres a reason (mentioned earlier) i dont think i can do the flush, as i dont have a vac to vap off all the solvent that is left behind, and if i close up the system after diy flush, to take to town, that solvent could get into the pump/oil

[BradC]

Maybe I've missed it but can you provide a bit more detail on periodic regas please (timelines etc)? I've often wondered why this is not a regular maintenance item, particularly given the problems/costs with total replacement/s.

It's complicated Gav. Anywhere between 2 & 5 years would be my target.

I don't buy new vehicles, so when I get a "new to me" vehicle a re-gas is on the first service list. Depending on how much comes out, I might do it again in 2 years, and depending on how much it's down determines how long I leave it till the next one. I've just checked the service record on the D3, and the last time I did it was 2018 (had a lot going on since then), so I'll put it on the list for the next service.

[PerthDisco]

It's complicated Gav. Anywhere between 2 & 5 years would be my target.

I don't buy new vehicles, so when I get a "new to me" vehicle a re-gas is on the first service list. Depending on how much comes out, I might do it again in 2 years, and depending on how much it's down determines how long I leave it till the next one. I've just checked the service record on the D3, and the last time I did it was 2018 (had a lot going on since then), so I'll put it on the list for the next service.

I had mine serviced last year for its first top up after 14 years. There was no trouble with it and it’s not noticeably better but I suspect it’s a bit stronger on the hottest day. They said it needed a little extra gas but nothing crazy. I seem to be well into extra time on my completely original system but fingers crossed.

[gavinwibrow]

It's complicated Gav. Anywhere between 2 & 5 years would be my target.

I don't buy new vehicles, so when I get a "new to me" vehicle a re-gas is on the first service list. Depending on how much comes out, I might do it again in 2 years, and depending on how much it's down determines how long I leave it till the next one. I've just checked the service record on the D3, and the last time I did it was 2018 (had a lot going on since then), so I'll put it on the list for the next service.


Thanks Brad, much appreciated. I think I'll work on 3.5 years ie during and midway between major services as a starting point. My services are usually time based as I normally don't do anywhere near the km service parameters.

[haydent]

So I had the idea to cut open the drier to see what it was like inside to hopefully give me some insight into what had been moving through the system.

Unfortunately cutting it open with a fairly thick bladed drop saw just filled it with metal so i wasnt able to tell what was old or new...

But I was surprised to see that only the very end has the desiccant in, also the flow does not go through the desiccant.

The welcome surprise I found though was that theres a screen filter in it. And when I checked the condenser with my air compressor, I confirmed that all flow goes through the drier tube, and thus screen filter.

So on finding this I felt more confident in deciding to not flush or replace anything in the cabin. At worse there will be some extra oil in the system, if there is a build up in the evap, but this should not damage anything. I just didnt want to risk making things worse by attempting a diy flush, mainly that there would be left over solvent in the evap that would get sealed in when i finish assembly and drive into town to get regas which might get it into the new pump/oil. Pulling the vac by tech should get it out , but I cant be sure.

Tommorow morning I will get re-gassed.



182718
(there is another 1/3 length of tube in between i cut out)

182719
Flow IN on right, left has the filter, so filtered on way out, leaving plenty of space in the cavity for buildup.

182720
The screen,

For anyone interested this is roughly how much space youd need to get the valve out, to get this much clearance you would have to remove the metal turbo output pipe nearby, something I didnt have to do.
182717

[josh.huber]

You can flush through the tx valve, I've done it.. but!!! When you do it. Use proper AC flush, that way you won't ruin seals in never never land.

Push it in slowly, let it sit. Then slowly push more in till it's dribbling out the compressor inlet. Let it sit for a while then start to push it out. Then start going both ways to break it up.

Keep going till it's clear.. Finish in the forward direction.

I use brake clean etc to clean out evaps if I can get the tx off easy. Like in commys etc. Don't use anything else.

When your done pushing the flush through etc.. Use heaps of air to make sure it's all gone. The AC guy just needs to vac it down for an hour and a half as opposed to an hour. In this heat. 1 hr would do.

When they say don't add oil directly to the compressor I'm pretty sure they mean the ports. People used to pour oil in the inlet and the compressor would hydraulic lock on start up and destroy itself. The sump is where I always fill them.

[haydent]

AC tech said he couldnt remember if he weighed it or not, but was confident he could get a indication of level by pressure, I will be asking for a weigh though from now on every few years.

Gassing went fine, he added 10ml oil and some dye with the refrigerant and now its making the cold stuff again, about 6.3 deg c at the vent.

I finished adding all my photos and notes here A/C Compressor & Condenser Change Pics & Notes (https://www.aulro.com/afvb/l320-range-rover-sport/293631-c-compressor-condenser-change-pics-notes.html)

Next to my car was a suburu, the compressor was right on top of the horizontal engine and the tx valve was at the engine side of the firewall [bawl]

In the hour I was there since 8am, people just kept coming with car AC problems...

[DiscoJeffster]

So in the end, you replaced the compressor, condenser and dryer, left the oil volume in the compressor as is, and the AC guy added some oil to compensate for the condenser and dryer change?

Nothing was flushed per se?

Not judging, just clarifying. I’m sure it’ll be fine.

[josh.huber]

Good write up, well done.

[haydent]

So in the end, you replaced the compressor, condenser and dryer, left the oil volume in the compressor as is, and the AC guy added some oil to compensate for the condenser and dryer change?

Nothing was flushed per se?

Not judging, just clarifying. I’m sure it’ll be fine.

Pretty much. AC tech says there is generally enough oil in a new pump for whole system. My understanding of the manuals mention of replacing oil if you replace a condenser or evap would be if you where just replacing either of those and not the pump. I think the amount he added was just the default setting on his system for a re-gas. Actually I realise now the manual says 130cm3 for total oil amount, and that IS 130ml or 130cc which is exactly what the pump has new, so the 10ml he add is extra plus anything left in the evap which may or may not be much.

But tech said its not really until you get like 2 or 3x the total system amount that you might get an impact from too much oil which does no damage just affect performance.

I did clean out the small bit of pipe from the pump to the condenser as it is easily removed, and I had both ends disconnected.

[haydent]

Here is a screenshot of my ac pressure from car off, to start car with ac on full.

182853

[scarry]

Here is a screenshot of my ac pressure from car off, to start car with ac on full.

182853

Looks fine after the 4 minute mark,but cycling at just over 3000Kpa before that doesn't seem correct?

But then again last time i played with auto air the systems had a glass and ran on R12.[biggrin]

See what the others think.You may have another fault that caused the compressor failure.
What were the ambient temps at the time?

[haydent]

Not sure, but when I had it regassed and first started running it the tech said the pressure was a high and asked if it had a thermo fan, i said i thought there was put not sure where. then it kicked in and the pressure became normal, so likely its just this, that the thermo fan hadnt started running yet, i can do another capture with this plotted too.

[LuckyLes]

That graph is a bit disturbing. I'd much prefer to see a set of gauges to work out what is actually happening.

[BradC]

Looks fine after the 4 minute mark,but cycling at just over 3000Kpa before that doesn't seem correct?

The manual says "Increases to 33 ± 1 bar (479 ± 14.5 lbf/in 2 ): the ATCM loads the A/C compressor again when the pressure
decreases to 23.5 ± 1 bar (341 ± 14.5 lbf/in 2 )." So looks like it's oscillating on the protective limiter.

I've *never* seen a SCT of >80C even under the worst ambient conditions.

[scarry]

The manual says "Increases to 33 ± 1 bar (479 ± 14.5 lbf/in 2 ): the ATCM loads the A/C compressor again when the pressure
decreases to 23.5 ± 1 bar (341 ± 14.5 lbf/in 2 )." So looks like it's oscillating on the protective limiter.

I've *never* seen a SCT of >80C even under the worst ambient conditions.

As i thought,cycling on the HP switch.

With 2.7l D4 i could see the revs the fan was doing on the Gap tool,but i am not familiar with the set up on the 3.0L,that is if it is a 3.0L.
But something is not correct,probably with the fan,air over the condenser is too low,at a guess.It isn't coming on at start when it should be.
We set our safeties for R404a/R22/448,etc, at 400PSI,run around 280PSI,depending on ambient,and this is 134a:eek2:

[josh.huber]

I wonder if thats how long it takes the viscous fan to speed up from dead cold?

It starts off normal, slowly ramps up due to no cooling then slowly comes back down. How long does it take the ECM to heat up the fan and get it moving.. Especially at idle.

Go for a drive with this log on, include fan command, I'll log mine the same this morning and report back.. It doesn't good.. But it might not be that bad.

[josh.huber]

Ok, just tested my D4.

On start up the fan was running at 1000rpm.. So basically 1:1. Never went past idle.. Pressures started at 140psi and creeped to 170psi but never any higher..I had the knobs on full cold with the windows down.

You can do it again watching fan speed or get a hose on mist and cool down the condenser at the same time. Also log other things, my air con saved list on gap has evap temp. Ambient. Pressure valve current etc.

Start with the fan

[haydent]

Here I was thinking it was a separate thermo fan turning on a minute or so after startup, but it must be the viscous ramping up.
I ran the test again (everything cold) and this time pressure didnt go so high, much more stable, will try again another day. Maybe this time due to ambient temp being a bit lower. Engine is TDV8

edit: (this graph is a bit off, car was only idled, so fan rpm is wrong and viscous control is not changing, yet fan speed is)

182881

[scarry]

Viscous fan may also have an electric overide,but i dont know how it operates,or what controls it.

At idle,to get the head pressure up to those sorts of pressures i would presume virtually no air would be going over the condenser.

[DiscoJeffster]

Viscous fan may also have an electric overide,but i dont know how it operates,or what controls it.

At idle,to get the head pressure up to those sorts of pressures i would presume virtually no air would be going over the condenser.

Viscous fan has electronic control managed by the ECU that allows it to go from slipping to 1:1 locked, using a rising voltage to increase the speed.

[josh.huber]

Here I was thinking it was a separate thermo fan turning on a minute or so after startup, but it must be the viscous ramping up.
I ran the test again (everything cold) and this time pressure didnt go so high, much more stable, will try again another day. Maybe this time due to ambient temp being a bit lower. Engine is TDV8

182881

Everything looks good now.. Happy days

[haydent]

You can see viscous control signal charted in last image, tests are done in carport at idle not moving. I will try again when warmer.

[scarry]

You can see viscous control signal charted in last image, tests are done in carport at idle not moving. I will try again when warmer.

Seems the fan got up to over 5000RPM?

Maybe I am missing something,or reading the data incorrectly?

They do a self test occasionally on start as well,and will roar away,which is normal.

[BradC]

They do a self test occasionally on start as well,and will roar away,which is normal.

Viscous fans all do that (electronic or thermostatic). When the fluid is cold, it's so thick the fan is effectively locked up. It takes 30 or so seconds for the fluid to warm to a point where there's the ability to control the fan. In my case it's usually backing out of the driveway and getting about 4 houses down the road before it starts to back off. If I hold it in 1st gear a bit longer it backs off quicker.

It's a good indicator of fan health also, because as they age and the fluid shears (or usually leaks) the severity of the startup roar decreases.

[DiscoJeffster]

Viscous fans all do that (electronic or thermostatic). When the fluid is cold, it's so thick the fan is effectively locked up. It takes 30 or so seconds for the fluid to warm to a point where there's the ability to control the fan. In my case it's usually backing out of the driveway and getting about 4 houses down the road before it starts to back off. If I hold it in 1st gear a bit longer it backs off quicker.

It's a good indicator of fan health also, because as they age and the fluid shears (or usually leaks) the severity of the startup roar decreases.

I have no roar anymore. Never. Not hot, not cold [emoji848]

[BradC]

I have no roar anymore. Never. Not hot, not cold [emoji848]

I'd be keeping a periodic eye on your temps, particularly on the hotter days. Unless they drop a seal, these things tend to "age gracefully", so you won't notice it's not doing the job until it no longer does the job. Unless the vehicle is under extreme duress, there is plenty of "spare capacity" to allow for wear and tear.

[DiscoJeffster]

I'd be keeping a periodic eye on your temps, particularly on the hotter days. Unless they drop a seal, these things tend to "age gracefully", so you won't notice it's not doing the job until it no longer does the job. Unless the vehicle is under extreme duress, there is plenty of "spare capacity" to allow for wear and tear.

I’ve suspected it for a while as the AC warms up when stationary in traffic and doesn’t come back until I’m moving. 13 years and 325k Km. Probably has seen better days

I’ll have to get the GAP out and take a look

[scarry]

Viscous fans all do that (electronic or thermostatic). When the fluid is cold, it's so thick the fan is effectively locked up. It takes 30 or so seconds for the fluid to warm to a point where there's the ability to control the fan. In my case it's usually backing out of the driveway and getting about 4 houses down the road before it starts to back off. If I hold it in 1st gear a bit longer it backs off quicker.

It's a good indicator of fan health also, because as they age and the fluid shears (or usually leaks) the severity of the startup roar decreases.

I am sure ours didn’t do it every start,when cold,although that is from an aging memory.🤣🤣

[scarry]

A bit more info here on the viscous fan,and it’s operation,and what the ECU actually looks at to control it.

DISCO3.CO.UK - View topic - How to check and confirm functioning of Electro viscous fan (http://www.disco3.co.uk/forum/topic39763.html)

[DiscoJeffster]

Seems the fan got up to over 5000RPM?

Maybe I am missing something,or reading the data incorrectly?

They do a self test occasionally on start as well,and will roar away,which is normal.

The fan is running higher than engine RPM as its pulley is smaller than the crank pulley assuming locked 1:1. Does sound high though unless the engine was being raced

[haydent]

maybe a glitch with gap, i ran again and it seems more accurate, also note the change in ac pressure with fan rpm (engine rpm not changed, just viscous change)

182891

[DiscoJeffster]

I logged a lot of mine today. The PWM viscous fan commanded was weird. Alway down to zero when stopped, and immediately ramped up between 10-30% when moving.

My GAP wouldn’t show me fan RPM - does that sometimes and doesn’t show me all the applicable logging options.

At idle, not moving, Evap temp was in the 5-8deg C, but while moving was in the 0-5 deg range.

When I was back in the garage, popped the bonnet and there was a decent flow from the fan at what it says is 0% PWM.

It definitely wasn’t roaring.

[josh.huber]

I logged a lot of mine today. The PWM viscous fan commanded was weird. Alway down to zero when stopped, and immediately ramped up between 10-30% when moving.

My GAP wouldn’t show me fan RPM - does that sometimes and doesn’t show me all the applicable logging options.

At idle, not moving, Evap temp was in the 5-8deg C, but while moving was in the 0-5 deg range.

When I was back in the garage, popped the bonnet and there was a decent flow from the fan at what it says is 0% PWM.

It definitely wasn’t roaring.

Ha ha, I got what seems to be an accurate fan speed, but n/a for control? Maybe we could combine our data

I always thought they operated like a normal viscous fan, and the ECM control was only to heat it up more if required, therefore making it faster, so yours having no pwm makes sense because it's already hot enough.

Please note, I have nothing factual to back that up

[haydent]

For additional airflow through the radiator matrix, particularly when the vehicle is stationary, there is an engine driven electro-
viscous fan unit fitted to the rear of the radiator. The fan is used for engine cooling and for Air Conditioning (A/C) system cooling.
This unit functions as a normal viscous fan, but with electronic control over the level engagement of the clutch. The Engine
Control Module (ECM), which determines the required fan speed, controls the level of clutch engagement. The ECM determines
engagement based on the coolant, charge air, ambient and transmission oil temperatures and the A/C pressure. The fan is
mounted using a left hand thread.
The viscous fan unit is electronically controlled by the ECM to optimise fan speed for all operating conditions.


Regulation of the coolant temperature is achieved via engagement of the electro-viscous fan assembly. This is controlled by a
Pulse Width Modulated (PWM) signal with a duty cycle of between 0 and 100%, provided by the ECM and derived from inputs
based on:
Coolant temperature
Ambient air temperature
Engine inlet air temperature
Air Conditioning (AC) system pressure
AC switch operation
Transmission oil temperature
Fan speed control is variable; however, because the fan is driven directly from the engine, the maximum fan speed available is
tied to engine speed. At high engine speeds the fan is progressively disengaged to protect the clutch unit. This system provides
very high levels of fan power, up to 5 kilo Watts (kW), with enhanced noise and fuel economy benefits compared to mechanically
controlled viscous fans.

NOTE: If the electrical connections to the viscous fan are disconnected the fan will 'idle' and overheating may result. The ECM stores the appropriate fault codes in this case.



lack of power idles it, so doesnt seem to be activating the slip, more the grip

generic google result:



Viscous drives control how fast an engine fan spins with remarkable accuracy. Oil is released from a reservoir into grooves that allow for increased or decreased friction depending how much cooling is needed.


The valve arm opens to push silicone oil in to the working chamber. As the silicone oil flows between the input and output clutch plates, it creates shear forces. This gradual buildup forces the two plates to spin at similar speeds, thus allowing a smooth change in the fan speed.



Since the fan slows when when high power is not needed, your vehicle gains horsepower and torque for better engine performance and mileage. When cooling is needed, the engine control unit (ECU) triggers the clutch, which puts the fan into faster rotation again.

[DiscoJeffster]

I’m guessing it goes to zero at idle to avoid making too much noise and ruining the lovely LR ambience [emoji4]

[haydent]

I’m guessing it goes to zero at idle to avoid making too much noise and ruining the lovely LR ambience [emoji4]

Yes, unless needed for the AC example, you will hear it if it ramps up, its sounds just like an electronic thermo fan you have on cars with sideways motors.

I looked to see if there was a way to trigger it in GAP but no, only monitor.

[haydent]

183042

I made another capture this time showing the pressure spiking and then dropping in response to the fan speed

[LuckyLes]

Something is not correct. With spikes like that you are risking losing another compressor. There is a lot more to diagnosing an a/c problem than looking at a snapshot showing a graph. What temperature is the suction line, how much superheat is dissipating across the condenser?
I feel that you may still have an ongoing problem and are risking your new compressor.

[josh.huber]

Test the fan, it's probably not what it used to be, requiring more ECM help then it should. Explains everything perfectly.

But I agree, if they keep running high pressure you'll shorten compressor life.. you sorry has made me think about my fan.. I've given this car heaps lately and not heard it roar? We are all over 10 years, I'm at 300k. Might be worth a refresh

[haydent]

i doubt there is anything wrong, but i will get the opinion of my ac tech.

im not worried as everything is monitored by the car:

if the fan rpm wasnt within the requested rate an error would be logged
if the pressure was too high it would cut the pump valve and if it was still too high it would raise an error

[josh.huber]

Whatever

[BradC]

i doubt there is anything wrong, but i will get the opinion of my ac tech.

im not worried as everything is monitored by the car:No it isn't.


if the fan rpm wasnt within the requested rate an error would be loggedNo it won't.


if the pressure was too high it would cut the pump valve and if it was still too high it would raise an errorYes it will; No it won't.

None of the conditions you've mentioned will log a code.

[scarry]

i doubt there is anything wrong, but i will get the opinion of my ac tech.

im not worried as everything is monitored by the car:

if the fan rpm wasnt within the requested rate an error would be logged
if the pressure was too high it would cut the pump valve and if it was still too high it would raise an error

An earlier post you did state the AC Tech said the pressure started a bit high,then the fan cut in,which is exactly what one of your graphs shows.
That should ring alarm bells.

Cycling at pressures over 3,000Kpa,on a safety device,will not take long to wreck something,and is far from normal.
That is well over double normal operating pressures.

Do whatever you want to do,we can only offer advice.It is your vehicle.

[LuckyLes]

You asked for advice and it was given, you then presented an anomaly and was advised that something was not as it should be. If I were you I would seek a second opinion from a professional. These systems are quite smart, but if there is a faulty component somewhere it can't diagnose itself, it can only shut down and will restart when the result of the problem ie. excessively high pressure drops because the compressor has stopped pumping.
You really need to know what is causing the pressure to spike.
Fixing something yourself if you have the capability is fine, but trying to fix something that you don't understand is fraught with danger.
This is bound to end up costing more than if you had gone to someone who knows these systems in the first place.

[haydent]

Just had my '01 d2 weighed, 450g left of 700g target. Cost about as much for "topup" as full refill though [happycry] works better now though


Tech said the pressure being high on rrs when the fan is not running is OK.

just noticed more past replies since "whatever" post, so will reply to them now, this thread is becoming more work than the car work itself [smilebigeye]

[haydent]

No it isn't.

No it won't.

Yes it will; No it won't.

None of the conditions you've mentioned will log a code.




The Engine Control Module (ECM), which determines the required fan speed, controls the level of clutch engagement. The ECM determines
engagement based on the coolant, charge air, ambient and transmission oil temperatures and the A/C pressure.


DTC B1B7885
System Pressure Pressure signal above allowable range

Condenser fault
Cooling fan fault


DTC B1B7884

System Pressure Pressure signal below allowable range
Refrigerant leak



DTC P049300
Fan Overspeed (clutch locked)

Seized viscous coupling
Fan speed sensor failure


DTC P049400 / P049411
Fan Speed Low

Viscous fan restriction
Viscous fan solenoid circuit high resistance
Viscous fan solenoid circuit short circuit to ground
Viscous fan solenoid failure


DTC P049512
Fan Speed High

Viscous fan solenoid circuit short circuit to power
Viscous fan solenoid failure


There are also more error codes if the fan speed sensor or control signal go out of range or performance characteristics.


You really need to know what is causing the pressure to spike.
its just the fan running or not, you can see that from the graphs


An earlier post you did state the AC Tech said the pressure started a bit high,then the fan cut in,which is exactly what one of your graphs shows.
That should ring alarm bells.

yes thats what i was showing with the graphs, and he just thought the thermofan wasnt working and started looking for one, but couldnt find it, then we heard what sounded like a thermo fan start and run, and the pressure dropped to normal, later i realised its just the viscous engaging or not rather than a thermo fan.


Cycling at pressures over 3,000Kpa

It must be able to handle it, as thats about the limit its programmed it to cut the compressor in and out at, and it didnt generate an error code so seems legit.

Bear in mind its not often you just start the car and idle it with the AC set to max, normally you start driving which will increase air flow due to movement and higher rpm.

[DiscoJeffster]

Hmmm. Doing the same with my AC, never gets to cutout in the same scenario. Idling in the Garage on Lo. Peaks at about half of your figure [emoji2369]

[haydent]

Hmmm. Doing the same with my AC, never gets to cutout in the same scenario. Idling in the Garage on Lo. Peaks at about half of your figure [emoji2369]

mine doesnt always do that, there is a chart above where it acts without the peak, i think it has something to do with the initial viscous state.

[scarry]

A manufacturer never designs an AC system of any type to cycle on a safety device under normal operation.

Although it is a Land Rover.....[biggrin]

[haydent]

Hmmm. Doing the same with my AC, never gets to cutout in the same scenario. Idling in the Garage on Lo. Peaks at about half of your figure [emoji2369]

actually did you plot fan rpm too, plz tell me if your fan rpm was ever less than engine rpm yet still had ~1k ac pressure


A manufacturer never designs an AC system of any type to cycle on a safety device under normal operation.

Although it is a Land Rover.....[biggrin]

its not purely a safety device, its general purpose to work with the variable output control valve, like a thermostat

though obviously if it didnt cut the pump out it would be an issue if the pressure kept raising, such as if the solenoid was stuck, the pump is just being cycled when it reaches the programmed max operating pressure, while it waits for the viscous or car/air speed to get going,

there would be another limit above that which would be the safety limit that triggers an error code

if one was really keen though dont bother (because you are exposing your system to higher than average pressures), you could disconnect the viscous control plug and watch the pressure [bigwhistle]

[scarry]

there would be another limit above that which would be the safety limit that triggers an error code

Are you sure about that?

[LuckyLes]

its not purely a safety device, its general purpose to work with the variable output control valve, like a thermostat

This is entirely incorrect. A hp cutout switch is not part of the normal operation of the system. Whoever told you that has no idea how an a/c system or a variable output compressor operates.

[haydent]

Are you sure about that?

well the fact i have not had that error come up ,and that error exists would suggest i have not hit that limit


its not purely a safety device, its general purpose to work with the variable output control valve, like a thermostat

This is entirely incorrect. A hp cutout switch is not part of the normal operation of the system. Whoever told you that has no idea how an a/c system or a variable output compressor operates.


its not a hp cutout switch, its a pressure sensor that feeds its data to the ecu that uses it amongst other data to make decisions about controlling the pump, viscous fan and other things.

[DiscoDB]

So haydent - have you actually ever seen it oscillating between the two high pressure set points again? Or was that shortly after you had put the system all back together?

Could have just been a case of the system recalibrating the required duty cycle for the pulse width modulator which controls the flow through the system.

And the compressor does have a seperate pressure relief valve (as a safety device). That is the one you hope never needs to do anything.

And not saying your system is or isn’t working as intended - but curious to know - is there actually still a problem with the a/c at present?

[haydent]

no problems. the time i graphed it doing this was not the first time it ran with the new pump, just once id gotten home from getting refilled, this was the first time i graphed it, at this stage not graphing fan speed, but you can see some pump signal changing at the peak. have not seen it do this again, but have not graphed that much

183225


ive also graphed it just getting high when the fan was not spinning enough

183222

and this pretty normal behaviour
183224

[shanegtr]

My D3 was/is spiking in a similar fashion at idle. A/C tech who last regassed it mentioned that the pressures where too high and that the fan was not doing its job. It does kick in and reduce the pressures so I hadn't gotten to concerned over it. Does make me wonder what is a normal operating pressure for these vehicles to spike to at idle?

I've just had the rear A/C evaporator fail so could be related to the pressure or judging by what the evap condition looks like I suspect it may be corrosion
183227

[LuckyLes]

A bit of a coincidence, but I have been travelling for the last 6 weeks, from Qld down to western Vic and now on my way home. The day before yesterday I felt that the a/c wasn't quite performing as it normally does. I normally set the temp to 22 and leave it there, hot weather cold weather or heat wave. So yesterday we left Yea and it was in the mid 30's outside, a/c cool but not what it should be, so I rang a number of places before I finally got onto a young guy in Wangaratta, who was prepared to check it out. He connected his gauges and ran it up, sure enough very high discharge pressure, high suction pressure, which I knew because I had felt the exposed suction tube, and viscous fan speed up and down. Degassed the system, evacuated and then regassed with the correct charge, and ran the system at about 1800 rpm to check the operation. Everything as it should be. 37deg celcius ambient, head pressure 250psi, suction pressure, about 25 to 30psi, doors open, so high load on the system, viscous fan operating normally, icy cold air from the vents, front and rear.
The op's a/c has a problem of some kind, and if not identified and fixed you will lose another compressor.
Good luck
LuckyLes
PS, this is the first time my a/c has been touched since the vehicle was new, 165000klm,s first registered Jan 14, built Nov13.

[shack]

A bit of a coincidence, but I have been travelling for the last 6 weeks, from Qld down to western Vic and now on my way home. The day before yesterday I felt that the a/c wasn't quite performing as it normally does. I normally set the temp to 22 and leave it there, hot weather cold weather or heat wave. So yesterday we left Yea and it was in the mid 30's outside, a/c cool but not what it should be, so I rang a number of places before I finally got onto a young guy in Wangaratta, who was prepared to check it out. He connected his gauges and ran it up, sure enough very high discharge pressure, high suction pressure, which I knew because I had felt the exposed suction tube, and viscous fan speed up and down. Degassed the system, evacuated and then regassed with the correct charge, and ran the system at about 1800 rpm to check the operation. Everything as it should be. 37deg celcius ambient, head pressure 250psi, suction pressure, about 25 to 30psi, doors open, so high load on the system, viscous fan operating normally, icy cold air from the vents, front and rear.
The op's a/c has a problem of some kind, and if not identified and fixed you will lose another compressor.
Good luck
LuckyLes
PS, this is the first time my a/c has been touched since the vehicle was new, 165000klm,s first registered Jan 14, built Nov13.So what was causing the issue?

[scarry]

So what was causing the issue?

Sounds like same intermittent fault as OP.

I doubt removing and filling with new refrigerant would make any difference,particularly as the AC in the vehicle had never been touched before.