300tdi Auto weirdness

[manic]

First proper run in the d1 saw us 2 1/2 out of melbourne up the Hume Hwy. Drive up was impressive, powered up all the hills, AC on, didnt slow once, all systems normal. Big grin!

Drive back, different story. Started to loose power up the hills and then kickdown became useless! Down to 3rd and it was like an engine brake, engine revs surging, power intermittent, unable to go above 80kph even when flat. One hill had me over in the emergency lane doing 60kph!

After a cool down at top of said hill, the rest of the journey was OK but mostly because it was flat.

No leaks, fluid level good. No smoke, or whooshing, not a boost leak. Im thinking blocked ZF filter?

[Woolly]

First thing to check is the turbo hoses. They delaminate inside and block the airflow. If you need one try Supercheap or Autobarn as they are a fairly common size.

[AK83]

or something like a split turbo hose to the IP pump or wastegate or whatever.

Sounds more like engine than transmission.

When you say kick down became useless, do you mean it didn't kick down, or that once it kicked down, it still had no power?


From my experience with my 300 tdi, driving up the hume:

Heading north:
Craigieburn bypass section, up the hill near Craigieburn as you approach the top of that hill and into Kalkallo where it merges back with the old highway, mine struggles up that way.
Same with the rise up to the Kilmore turn off once past the Shell servo and into the 110k/h zone.

If I set boost compensator to give me more fuel with boost, I can also fly up those two sections without slowing, in 4th locked up torque converter and all, BUT my exhaust gets very hot .. I chicken out and back off.
On a cold day(ie. 15°C ambient) the problem is much less of a problem.

Q. do you have an EGT gauge to be sure someone hasn't tweaked the fuelling for power with no regard to exhaust temps?
and do you have a full exhaust(ie. both mufflers) fitted.

I found on long drives the removal of the rear resonator created 90% of the low frequency drone noise that makes a drive not so pleasant.
So I had a rear muffler(some aftermarket crap) re fitted to get rid of that issue, but doing so has mucked up the EGT/Power balance again.

My next 'tweak' will be to have a decent exhaust place find me a good balance between power and droning exhaust ... via a better performing rear resonator.
I won't go back to no resonator, as the droning is my priority.

[manic]

Kickdown action was working fine but once down to 3rd it slowed faster than it would have staying locked.

I dont think the motor as been fiddled with in regards to fuelling. None of the caps on the IP are damaged. It is all stock in regards to exhaust, intake and guages.

That said on the drive north it was the best TDI motor ive ever experienced. Smooth, no smoke, did not drop off the speed limit once and this is with 235/85s messing with the gearing. Going up those hills you mention with AC on, speedo on 110, gps reading 115, no kickdowns and foot not on the floor. Does make me wonder about egts though! No sign of temp guage moving, always sat just below half.

I pulled all the intake hoses and all look OK. Elbow at turbo is very soft and they all look fairly old so I ordered some silicone replacements and a good set of clamps.

Removed the intake manifold and found the gasket was tired, possibly had a small boost leak there. Pulled back the exhaust manifold to change gasket and found all the manifold bolts were just nipped up. Doubt any of this is enough to cause the amount of power loss I experienced but worth the check.

Im going to change the fuel filter, clean out the sedimenter, renew the auto filter. See how she goes!

[donh54]

Don't ever, EVER, EVER rely on the factory temperature gauge!
By the time it moves off half way, the head gasket is probably gone, and a few seconds later you're up for a new cylinder head!
Aftermarket temp gauge and egt gauge are number one priority, especially if you are looking to tow anything, or going to keep up with traffic up hills.

[trout1105]

Don't ever, EVER, EVER rely on the factory temperature gauge!
By the time it moves off half way, the head gasket is probably gone, and a few seconds later you're up for a new cylinder head!
Aftermarket temp gauge and egt gauge are number one priority, especially if you are looking to tow anything, or going to keep up with traffic up hills.

I agree the landrover temp gauge reads Cold, Normal and Buggered engine Once it starts to move north of halfway you are already in trouble.

[AK83]

....

I pulled all the intake hoses and all look OK. ....

What about all the boost hoses?
Hose from turbo to wastegate, and boost compensator at the injection pump.

So you get kickdown, eg. to 3000 RPM, then no power once that happens. This sounds like the typical lack of boost pressure issue.

Now that you're back home, have you driven around to check power?
Does it only lose this power in kickdown from 4th to 3rd? ie. is power through 1st to 2nd still ok?

Like Don said, dash temp gauge is all but useless.
Mine sits fine until the actual coolant hits between 103-105°C.
No slow steady climb to warn you that coolant is running high.. mine indicates just a mil or so below the centre of the gauge and then at 103-105ish .. it then shoots up close to the red.
Unless you always have one eye on the gauge, you have no idea.

And like I said with mine, only time I get any temp higher than about 83°C(ish) is with A/C on at freeway speeds.
Without A/C on, and recently having tested in deep sand too .. it just doesn't move past it's normal 83-ish.

I guess check the free and easy stuff.
Wastegate lever and it's vacuum port(inject with compressed air). Does the lever move? .. etc ..

[manic]

I know the guage read out is not linear so any upward movement is a call to pull over.

I have a spare sender so Im curious to test the readout on a camping stove. If 100c is a noticable rise it will be good enough for me.

On the defender I have a CH and vdo coolant guage. I back off the accelerator when coolant gets over 100C, which can happen if flogged on a hot day. No major.

You know, I did forget to check the small hoses for FIP and wastegate , thanks!

Not had a chance to drive it since, should get onto it this weekend

[trout1105]

I know the guage read out is not linear so any upward movement is a call to pull over.

I have a spare sender so Im curious to test the readout on a camping stove. If 100c is a noticable rise it will be good enough for me.

On the defender I have a CH and vdo coolant guage. I back off the accelerator when coolant gets over 100C, which can happen if flogged on a hot day. No major.

You know, I did forget to check the small hoses for FIP and wastegate , thanks!

Not had a chance to drive it since, should get onto it this weekend

I have a scan gizmo that uses the OBD2 port of my D2a and when my head gaskets were buggered I had readings of 115C-120C before the gauge started to read Hot and it went from 90C to boiling very fast.
IMHO the gauge on the dash of the D2 is bloody useless.

[manic]

I have a scan gizmo that uses the OBD2 port of my D2a and when my head gaskets were buggered I had readings of 115C-120C before the gauge started to read Hot and it went from 90C to boiling very fast.
IMHO the gauge on the dash of the D2 is bloody useless.90c is pretty much normal operating temp, if the rise to 120c was fast you would be lucky to catch it even with a good guage.

What caused such a rapid overheat?

[trout1105]

90c is pretty much normal operating temp, if the rise to 120c was fast you would be lucky to catch it even with a good guage.

What caused such a rapid overheat?

I had blown a head gasket [bawl]
My OBD2 gauge picked up the high temps WAY before the dash gauge and it allowed me to get back home before I completely destroyed the engine.

[AK83]

90c is pretty much normal operating temp, if the rise to 120c was fast you would be lucky to catch it even with a good guage.

....

Not necessarily!

eg. is my D1, normal operating range is 80-83C.
In really hot weather and in arduous going(eg. up steep hill, or heavy sand, I've seen it get to 85, but it always drops back down to it's preferred 83-80C.

Turn AC on tho, and I get a steady rise to 90 quite easily, and under harder load it climbs to the max I've see at 105C.
It could have risen more, and I dare say it would have, but I chickened out, turned off AC and slowed right down, and would have pulled over had it not started to drop.

Had I relied only on the dash temp gauge .. it doesn't seem to operate between the half way zone and the red zone.
The needled basically only works up to just under the halfway area, then must rise to the red zone in a matter of only a few seconds.

if it indicated a slow and steady rise as the coolant approached 90, then 95, and so on, it wouldn't be a problem at all .. it'd be easy to manage keep an eye on it and decide what the best action would be considering the conditions ahead and so forth ...

As it is tho, it's unusable, shows everything is OK, and only moves again once up to about 103-105C range.

Different matter tho if the coolant was suddenly all lost tho, as you say you probably couldn't catch that situation unless an alarm was fitted to show the coolant loss.

FWIW with mine at the moment, the heating up issue with A/C on is whilst on the move over 80k/h. Up to 80 k/h it's fine. hovers in the 88-89°C range, and can drop back to about 85-86°C. I'm guessing it's the 88°C thermostat doing it's job.
So I'm looking at radiator and thermofan mods to see if I can get it to maintain cooler coolant temps with the A/C too.

[manic]

Not necessarily!

eg. is my D1, normal operating range is 80-83C.
In really hot weather and in arduous going(eg. up steep hill, or heavy sand, I've seen it get to 85, but it always drops back down to it's preferred 83-80C.

Turn AC on tho, and I get a steady rise to 90 quite easily, and under harder load it climbs to the max I've see at 105C.
It could have risen more, and I dare say it would have, but I chickened out, turned off AC and slowed right down, and would have pulled over had it not started to drop.

Had I relied only on the dash temp gauge .. it doesn't seem to operate between the half way zone and the red zone.
The needled basically only works up to just under the halfway area, then must rise to the red zone in a matter of only a few seconds.

if it indicated a slow and steady rise as the coolant approached 90, then 95, and so on, it wouldn't be a problem at all .. it'd be easy to manage keep an eye on it and decide what the best action would be considering the conditions ahead and so forth ...

As it is tho, it's unusable, shows everything is OK, and only moves again once up to about 103-105C range.

Different matter tho if the coolant was suddenly all lost tho, as you say you probably couldn't catch that situation unless an alarm was fitted to show the coolant loss.

FWIW with mine at the moment, the heating up issue with A/C on is whilst on the move over 80k/h. Up to 80 k/h it's fine. hovers in the 88-89°C range, and can drop back to about 85-86°C. I'm guessing it's the 88°C thermostat doing it's job.
So I'm looking at radiator and thermofan mods to see if I can get it to maintain cooler coolant temps with the A/C too.




FWIW with mine at the moment, the heating up issue with A/C on is whilst on the move over 80k/h. Up to 80 k/h it's fine. hovers in the 88-89°C range, and can drop back to about 85-86°C. I'm guessing it's the 88°C thermostat doing it's job.
So I'm looking at radiator and thermofan mods to see if I can get it to maintain cooler coolant temps with the A/C too.

Doesnt sound like you need those mods. 88C is the operating temp the thermostat is there to maintain. If your normal is 80-83C , you are running cold! Are you sure you have an 88 stat (stuck open?) and your guage is accurate? :)

[AK83]

Doesnt sound like you need those mods. 88C is the operating temp the thermostat is there to maintain. If your normal is 80-83C , you are running cold! Are you sure you have an 88 stat (stuck open?) and your guage is accurate? :)

Yeah, heard that before a few times.
From my experience(and this is just a personal preference) .. I think it's rubbish.
I prefer it to run at this 80-83C range if that's what it prefers to do.

Temps also recorded with an IR thermometer along the head. Some points reach 90-ish deg(give or take a couple), but most of it records in the 80-85 range, so I'm confident that the coolant gauge is accurate enough.
ps. I'm no actually interested in the absolute coolant values, more so the changes.

Thermostat was changed to a tridon 88C version(I also got a 78C version too, but ATM have no plans to use it)
Old thermostat was a Waxstat version barely opened up to allow flow, compared to the new Tridon, but irrespective the 300Tdi still ran at a consistent 83. Now it's more like 83, but it can get down to 80 as well. (so I quote it as 80-83)

Where it causes me concern is that with the A/C it prefer to run at over 100°C if I don't manage it.
That is, if I didn't have the coolant gauge, I'd just be happily motoring along with the coolant running at over 105C every time I run the A/C.
A/C is nice to have, but not a vital thing for me.
Those higher temps with the A/C on are only at 80+ k/h, hence why I'm leaning towards a non optimal radiator flow.
The other point could be the bullbar(TJM style), possibly not directing enough flow from underneath or something.
I don't think that the front isn't impeded a lot even tho there's a short lightbar. Lightbar has a good flow design.

But this heating up with A/C on isn't limited to 80+ speeds, it also happens just under a load, eg. uphill climb windy road even at 40k/h.
On the downhill, it cools down quickly tho.

But in terms of operating temps... I'm happy with 83 as an average. I also have an oil temp gauge, and it could be a bit inaccurate, but generally returns 60-65C.
Will climb up with the added heat that the A/C issue causes too, and take a lot longer to cool down than the coolant does.

When I tested the thermostats:
Both in the same bucket of boiled water, adding boiled water to maintain temps and stuff.
Tridon reacted immediately to the hot water, and opened much quicker when freshly boiled water was introduced.
Waxstat barely move a half a mil. Took minutes to finally start to open(with 100°C water added continually on it).
Water chucked and test started again, Tridon opening, water on waxstat and barely any movement. This is the waxstat that had the coolant running at 83.
Finally the waxstat would open to what seemed to be it's full flow, barely 2mm or so, and held it there as cold water was added to bring water in the bucket to the mid 80s.
Tridon on the other hand started to close up from full flow. Waxstat hardly moved again.
With no water, was the only time the waxstat reacted quickly, and closed up as quickly as the tridon did.

Only thing I'm finding hard to test is the temp of the radiator at top and bottom.
I may get some stick on probes and some gauges to show a rough idea of what it's doing as I'm driving along.

Obviously the A/C condenser is transferring it's additional heat into the coolant rad.
What's curious tho is that even in high 30's heat with no AC, I barely see any increase in coolant temps either, even under a hill climb type load.

Anyhow, back onto your issue: have you had any luck tracking down a likely culprit?

[manic]

Still waiting for the weekend, till then its just chat.

Tridon thermostat, thats good info. Will get one next coolant change. Faster reaction cant be bad.

As for temp monitoring I think I will go for a two stage alarm set up. I dont want an extra guage screwed into the dash if I can avoid it.

The thermostat housing has a fan switch for the condensor. I beleive it cuts in somewhere around 100C. Im thinking of replacing it with a dual switch

In 105°C - out 100°C
In 120°C - out 115°C

First switch activates condenser fans and lights an orange warning LED on the dash which will tell me to ease up and watch out.

Second triggers a CHECK ENGINE alarm that is very loud and cannot be ignored.

The AC has a 115C cut out, so land rover must have considered this point very close to the upper limit! When it cuts out the temp should fall so no need to terrify the driver with an EMERGENCY alarm at this point. But if it continues to rise to 120C THE EMERGENCY CHECK ENGINE ALARM GOES OFF!!

The amber warning will be enough for me, the red alert is there to stop a guest driver from driving it to destruction.

[AK83]

Still waiting for the weekend, till then its just chat.

[QUOTE=manic;2751792]Tridon thermostat, thats good info. Will get one next coolant change. Faster reaction cant be bad.

Part number I got was the TT388-190(88°C) and a TT388-180(78°C).
I looked for markings on what they each were and couldnt' see nothing till I eventually looked deep into the tubular copper valve bit, and it's hard to see but it is marked.
Not only was it faster reacting, but after sitting for a few minutes in the boiled water(and sometimes adding fresh boiled water), the tridon showed about a 10mm gap betwen body and valve, whereas the Waxstat was barely 2 or 3mm .. so better flowing(or less restrictive) from the Tridon.
Stupid me, didn't take pictures whilst I was at it, and now I can't locate the old Waxstat one either.
I may end up getting a new one just to satisfy my own curiosity on whether the old Waxstat was just degrading itself to a non opening condition, or is that it's design.


As for temp monitoring I think I will go for a two stage alarm set up. I dont want an extra guage screwed into the dash if I can avoid it.
I'm the same re: gauges. Not a fan of the million and one gauges look, so I chose the 1Gauge. Just the one decently sized LCD gauge(about 3"), which fits perfectly in the overhead blanking console. Cabling was easy, the brain box is in the drivers drop down lid for the fuse box access etc.
Displays 7 gauges if you have a dual battery setup(6 if not), came with all the proper(VDO) sensors required and K type thermocouple .. and I just had to get adapters to suit the sensors.
For $500 I think it's good value. More than anything about it is that I liked it's logging ability, although I'd prefer if it could also keep time for that as well.


The thermostat housing has a fan switch for the condensor. I beleive it cuts in somewhere around 100C. Im thinking of replacing it with a dual switch

In 105°C - out 100°C
In 120°C - out 115°C

First switch activates condenser fans and lights an orange warning LED on the dash which will tell me to ease up and watch out.

Second triggers a CHECK ENGINE alarm that is very loud and cannot be ignored.

I can't remember if the A/C thermo fans cut in at or near 100°C when I've had it that hot. Like I said, my priority is to manage it as I can.
Coolant temp rises slowly unless the road is steep, no matter the gear, or EGT reading. But with A/C off coolant drops quicker than if I leave A/C on and the road levels out or starts to drop.


The AC has a 115C cut out, so land rover must have considered this point very close to the upper limit! When it cuts out the temp should fall so no need to terrify the driver with an EMERGENCY alarm at this point. But if it continues to rise to 120C THE EMERGENCY CHECK ENGINE ALARM GOES OFF!!

The amber warning will be enough for me, the red alert is there to stop a guest driver from driving it to destruction.

Again, I chicken out wayyy before those temps are achieved. Max I've yet seen has been 105C, and the first time I pulled over to be sure I wasn't loosing coolant. In fact did that a few times, before I realised what was going on with the A/C.
Engine never felt overly hot, but definitely was hotter in the hoses and felt much more pressurised than it usually feels.

Another thing I liked about the 1Gauge was it's ability to drive both relays and warning lights as well as those other things I liked about it.
Can connect up to 3 relays for the various sensors/probes and two warning lights if needed. Kit comes with two leds in chrome bezels too, but yet another thing I like about it's operation is that once configured(easy to do) to set an upper limit to any sensor value, that section of the LCD display inverts colour as a warning too.

So, as an example EGT is set to 695(as I'm going by the accepted 700C upper limit that many have advised about).
The LCD is white on blue, and up in the blank console above the rear view mirror. Without taking eyes off road, when the EGT square on the LCD inverts, it's easy to notice in your periphery vision. That is I can't actually distinguish the value itself, the change from white on blue to blue on white is the distraction.
Since I got mine, the 1Gauge chap has also allowed new LCD options for colour, being green/yellow and white/black.
I would have preferred white on black (I think his does black on white).
Another slight loss of points on the product is that out in the deep bush with no lights whatsoever whilst driving, I find the display a little too bright, even tho it does dim when the dash lights come on(ie. parkers or headlights).
The chap did explain that it can be modded to make it a bit dimmer if wanted, and would email me the details on which resistor to change, but it's not a major issue.

I do have a bit of a write up on it .. search 1Gauge on here .. should come up.
(note! .. my actual install is a bit of a bodge, in that the console panel cutout is very rough, so it looks badly home made. But the panel was badly botched anyhow when I got the D1 due to an owner having installed a compass up there).

I reckon install shouldn't take more than a couple of hours all up. The hardest part, and why mine took about two weeks to get it fully going, was figuring out what adapter types were needed.
In the end for the coolant, I went with a 1/4BSP brass plug with a 1/8th NPT access for the coolant sensor(longer type) to fit into the thermostat housing plug access(replaces the weak plastic bung there anyhow).
For oil temp, I used the shorter VDO sensor, and as I also wanted oil pressure, I needed two adpaters to also keep the standard oil pressure warning light sensor as well.
That sensor uses a M10 fitting. If you forgo the std oil sensor, a second adapter isn't needed. But the adapter is then a simple $20 M10 to whatever sensor size you choose(1/8NPT, or M10 and I think even M12).

May sound expensive at $500, but considering the price of a Madmad, and that the gauge price doesn't include any sensors or adapters .. it's much cheaper overall.

[manic]

Yeah I think 1gauge would be the go if I wanted to properly monitor the D1. But Ive picked her up at 20 years old with no mods, and Im not looking to upgrade or modify, just restore and maintain.

Whilst on a stock tune I think she'll be alright with dash warning lights plus a low coolant and high temp alarm. Thermo switch and wiring is all I need as I already have the check engine light and buzzer tapped.

The defender has a madman and with all the mods and tune ups I pretty much drive to the readouts when on the highway. But it can be distracting and all the extra wiring puts me off doing the same in the D1. I want to keep this one simple as. If something major is wrong it can flash a light or buzz me, otherwise it can get on with it like it has for the past 20 years.

[manic]

New hoses arrived just in time. $39 delivered - thank you China! :)https://www.aulro.com/afvb/images/imported/2017/12/429.jpg

[Robmacca]

Don't suppose u can share the eBay link?


New hoses arrived just in time. $39 delivered - thank you China! :)https://www.aulro.com/afvb/images/imported/2017/12/429.jpg

[manic]

Don't suppose u can share the eBay link?
EBAY search for
"silicone hose kit for land rover discovery 300tdi"

[AK83]

ps. I hate when you look for something and can't find it. Haven't been able to find the old waxstat stat for a while, and today I went looking for another 3/8 drive ratchet I know I have somewhere. It was inevitable that I couldn't find it, but the consolation was I found the waxstat! :d

Tested again in the bucket(icecream bucket) with freshly boiled water) and same observation as before.
IR thermometer recorded 96°C directly on the stat, and only about a 2, maybe 3mm opening. I preheated it a couple of times too to get it already hot and added freshly boiled water..
Thought to myself I'm gunna get this thing to open up properly,, even if it scalds me trying!
So I popped it in the pot over the stove and finally, it started coming good.. So it does eventually open up fully in vigorously boiling water, but it's an ordeal to get it so.

So my earlier comments re the waxstat not opening fully have to be retracted due to a lack of trying before.
But the Tridon still do react much quicker to both contact with hot water, and contact with cold water once fully open.
The waxstat also take twice the time to close from fully open(in the pot) to dunking in the cold water in a bucket too.

Another thing to note about the Tridon, is that there is a stamping on it marked Motorad (http://www.motoradusa.com/fail-safe.aspx), which is a auto parts thermostat manufacturer from the US.
So I'm assuming that Tridon buy them in for this particular model of thermostat.

[edddo]

I have just replaced my old 88 Waxstat for a new 88 Tridon.
I tested them both before putting the new one in.
The old Waxstat started opening at about 70-75 and was fully open by about 90.
It was fully closed at 70 on the cooldown.
The Tridon started opening at about 85 and was fully open by about 90.
It was fully closed at 80 on the cooldown.
I couldnt see that there would be much of a difference in the flow rate when both fully open.
The early opening on the Waxstat partly explains the very long warmup time especially in winter.
I doubt that the Tridon will have the motor running any cooler - based on what I observed.
Will see over the next few days.

[manic]

Ok so fuel filter changed, sedimentor had some gritty **** in the bottom but doubt either caused the issue.

Manifold gasket wont arrive till monday, will go on with the new hoses and then test drive.

Tried to change auto filter but realised it was not as straight forward as I imagined so only a fluid refresh in the end. Have a feeling I may have to come back to that! I fear recent fluid change has dislodged crud into the filter causing low pressure slip through the gears.

Inspected wastegate and hose to IP. All looks OK there except the IP line has been rubing on the injector lines. Not right through but not far off!

Looked for other rubs and boy are there some hose rubbing issues in this engine bay. Seems like a lot of the hose retainer clips are broken. Needs a good tidy up!

https://uploads.tapatalk-cdn.com/20171216/20ee1dc7c03b28c5d19e27dc28bdd638.jpghttps://uploads.tapatalk-cdn.com/20171216/aff28c076e0a9611918455d34bb0484e.jpghttps://uploads.tapatalk-cdn.com/20171216/02bede3ea8208778a0fe8f11220be8d2.jpghttps://uploads.tapatalk-cdn.com/20171216/f6eb37845a6ab45d0b463206d181f734.jpg

Oh, and the heater hoses that run around the back of the head is touching the back of the rocker cover and wearing thin! Is that normal land rover rubbish or am I missing a retainer back there too?

[AK83]

....

Oh, and the heater hoses that run around the back of the head is touching the back of the rocker cover and wearing thin! Is that normal land rover rubbish or am I missing a retainer back there too?

Ah! .. Ok then! It may be normal(landrover rubbish), as one of mine is the same.

I popped in some noise insulation on the bulkhead a while back(just push fitted it all and wedged it between pipes and stuff).
Had a bit left over and so used a small piece to separate the heater hose from the corner of the head.
I have a full set of silicon hoses that I got over a year ago now .. still too lazy to fit them up, but got it all on the basis that I really hate those 'amalgamated' hose off hose type designs like the main large rad hose, and that this one heater hose of mine has been rubbing for quite a while and I thought would have popped by now(but hasn't).

One of the things I prioritized when I got mine mid last year. Check all rubbing spots in terms of hoses and badly placed wiring .. and remove unnecessary addons too.

Eddo: on the flange of the waxstat could be a very small circle with a number inside the circle. Mine says 88(so it's a circle with an 88 inside it) hard to read, but a magnifying glass makes it easier.
I'm curious as to whether someone used a 78°C stat in yours.
Mine is the other way round. Hardly opens at 83(maybe a mm).

[edddo]

Hi Authur
The waxstst is also an 88 (about 9 yrs old) so probably just malfunctioning albeit safely....or maybe just differently to the Tridon.
I am not clear on how exactly an 88 should operate ie opening temp, what temp it should be fully open, the gradient of degree of openess vs temp etc.
I assume manufacturers would have this data.

I am not going to change anything else until I get the radiator replaced or reco’d now.
It was rodded about 9 yrs ago. It is the original one so i will probably renew i think.

[manic]

Gaskets delivered on a Sunday - thank you Christmas!

Fitted with new silicon hoses, all torqued up. Bonus time for rocker breather clean out and tappet clearance check, barely any adjustment needed. Not suprising considering how smooth and zippy it has been.

Test drive saw 3 selected and foot planted from stand still. Lag until boost kicked in and then shot off , continued to shoot past 80kph no problem. No motor way or hill to test on today but car sounds and behaves exactly as it was on the last run when all was going so well. No better, no worse.

It still has a pronounced turbo whistle which must be the flexi joint on the dump pipe. Its a little shredded. So I dont think manifold gasket was the issue.

Back up the Hume for Christmas so will see how it goes on that same hill. Id be confident if I had managed to change the transmission filter!