D3 Aircon compressor

[Airmech953]

I'm partway into removing the aircon compressor on my 2005 D3. The Haynes book is pretty vague about the process - i have removed a lot of pipework around the area and still can't remove the turbo inlet pipe. I'm looking at removing the upper suspension arm to improve access, but it will only be a marginal improvement.
I will also be installing a new condenser with receiver drier.
Is it normal practice to flush the evaporator and pipelines? If so what do people use?
Should the new compressor be filled with oil on installation, and what quantity should that be?
Is anyone local to Melbourne who has done this job and willing to have a phone hookup to talk it over?
Any info is appreciated.

[DiscoJeffster]

You are going to get a lot of opinions, so here’s mine. I flushed my front and rear evap using a flushing tool on my air compressor. I used shellite as my flushing agent. Flushed back and forth through both evaps. They say you can’t/shouldn’t flush through the TX valve, but I did and many do.
Lot of air afterwards to dry out the shellite.

As for oil, you should use AT LEAST as much as the design says. Your manual will tell you. I used a bit more to be sure. I had about 100ml in the compressor - maybe a bit more - in the sump. I drained it from new, measured how much was in it, then refilled it with the amount I wanted. I then added enough throughout the system to give me at least what was needed, plus I added an extra 30ml I think. It’s meant to be 160ml - I was around 190ml all up. I added some into the condenser, some into pipework.

New, genuine o-rings at any point I opened. New schrader valves on your connectors.

I installed a new compressor, condenser and drier. Had a shop degas and regas.

Getting the compressor out is a battle. I took the front off my D4 and most of the side to get mine out. Didn’t have to remove any suspension components, but did remove the power steering pump.

Good luck!

[PerthDisco]

When I accessed the plastic coolant inlet very close to the AC pump i also changed all turbo hoses to silicone.

I removed upper arm to get a better shot at the retaining bolt.

You need to remove all the heat shields and from memory there’s is a well hidden very fiddly bolt to release the solid turbo hose joiner in order to get that out of the way. Lots of bleeding from the hand region I recall.

Shane Shed did a video of changing his on YouTube. I have that very same comp in my spares after he parted out the car soon after that.

[BradC]

I was going to comment, but DJ covered pretty much all of it, so just a general comment or two. Too much oil "slightly" impairs the efficiency of the system, while too little eats compressors. Doesn't *really* matter where the oil is added provided you don't slug it into the suction side of the compressor. It gets moved around within minutes of firing up. In the past I've just put it into the compressor sump.

Shellite is also what I use for flushes, just make sure it's *all* really out before you gas up.

[DiscoJeffster]

I was going to comment, but DJ covered pretty much all of it, so just a general comment or two. Too much oil "slightly" impairs the efficiency of the system, while too little eats compressors. Doesn't *really* matter where the oil is added provided you don't slug it into the suction side of the compressor. It gets moved around within minutes of firing up. In the past I've just put it into the compressor sump.

Shellite is also what I use for flushes, just make sure it's *all* really out before you gas up.

Yeah, I erred in the side of caution and used a little more oil. Probably unnecessary, just felt better about it.
I had Josh Huber advising me. He also got me the parts. Legend.

[BradC]

Miss Josh. A lot. He was very knowledgeable and helpful. I can only hope he's gone to somewhere that pays him a ****load where he can't risk reputation by posting here.

[scarry]

Shellite is also what I use for flushes, just make sure it's *all* really out before you gas up.

Or on bigger systems we use CPS Proflush,which seems to have R11 in it.
R11 was the best flushing/cleaning agent for Refrigeration systems,and other cleaning applications by a country mile,we could get it in 200L drums back in the day.

The 45KW Ac system we recently had that was full cooling tower water[bigsad][bigsad],we used CPS Proflush,and it seemed to work well.

[Graeme]

I had no trouble removing or installing one recently on a 3.0 D4, following the LR WSM instructions which included removing the inner guard. The PS pump wasn't removed, nor was any suspension component other than disconnecting the height sensor arm as it was across the middle of an access opening. I couldn't pull the coolant inlet hose off the housing so pulled the housing out still attached to the hose. Similarly I couldn't push the new hose onto the installed new housing so then fitted the new hose with the new housing already attached, albeit with the clamp not tightened. The job takes time though.

[BradC]

Or on bigger systems we use CPS Proflush,which seems to have R11 in it.

Perhaps this is why you need a refrigerant handling license to get it. R11 was an awesome flush, but it's still a CFC and "bad stuff". Shellite will remove *all* refrigerant oil but it takes a lot to get out. Something like Iso-Pentane would be better (same solvent action but much lower evap temperature), but I can buy Shellite at the green shed.

[Airmech953]

Ok, I've finally got the aircon compressor out. I didn't remove the steering pump but had to remove the line from the reservoir to the steering pump as well as the upper control arm, heat shields and turbo inlet pipe. The locating dowel on the new aircon compressor was about ten thou bigger than the location hole on the original high pressure hose, so I had to remove the new pump to rectify that!
I charged the new with 200ml of the specified oil before fitting. I injected into the inlet (larger) port on the compressor, then reread the note from BradC who advises not to do that. I have manually rotated the compressor a number of revolutions. Should I suck some oil out of the inlet port and load some into the outlet port via the hose which is now attached or will it be ok as is?
I did buy a flushing tool and special cleaning fluid from Wurth so I have flushed all of the lines and I'm fitting a new condensor and drier.
Overall this is not an easy job, access and visibility are both difficult.

[DiscoJeffster]

You should have either put the oil in the sump of the pump or distribute through the system, not into the inlet or outlet of the pump. Did you drain the pump to measure how much oil was already in its sump? If you’ve added 200ml on top of what’s in the sump then there’s much too much oil in there. They ship with around 80ml in the sump.

[BradC]

I injected into the inlet (larger) port on the compressor, then reread the note from BradC who advises not to do that. I have manually rotated the compressor a number of revolutions. Should I suck some oil out of the inlet port and load some into the outlet port via the hose which is now attached or will it be ok as is?

If you can see oil in the inlet port, just continue manually rotating by hand until it's *all* gone and then some. In the old days this was standard practice because you could slowly push the oil through the system, but with a variable displacement compressor the compressor is going to default to 5% displacement which means it'll take quite a few rotations to move it all through rather than the 10-20 you could use on a fixed displacement.

The risk is a cylinder full of oil at speed can shatter the reed valves on that cylinder. Compressors don't like large quantities of liquid for that reason.

I'd err on the side of caution and give it plenty more hand rotation before you put the belt on.

All the swashplate compressors I've seen have had a fill plug on the top. Pop the plug and invert the compressor to drain the oil into a beaker for measurement/assessment, and drop the right amount of oil in to fill. If the oil that comes out is clean and clear you measure what came out. New compressors come oiled up, so you drain the oil and only put back the same qty that came out of the old one. The old twin tecumsehs had a proper sump with a drain plug.

If your system was contaminated then all bets are off and you start from scratch.

My old Volvo was full of grey death. While I had it apart for a flush I also replaced the original tube & fin condenser with the largest parallel flow that I could make fit. More condenser, more hose and more total system volume. I started with the rated oil load (half in the compressor and half in the accumulator). Then the deal was run the system for 15 minutes at full load to distribute the oil, drain the compressor and adjust the oil qty until it was per manufacturers spec.

I wouldn't want to do that on a D3/4, but on the Volvo the compressor could be removed / replaced in ~10 minutes.

Just be careful because those reed valves are pretty fragile.