Unexplained coolant loss

[martyw]

Hi, I have a 2003 Rover 75, 1.8 turbo with 70000 recorded miles. I bought the car with an hgf / water lose problem and have recently replaced the HG, water pump, belt and tensioner and oil pump. The engine has run for 1 and a half hours in total and only travelled 6 miles and that was to get the MOT done which it passed with flying colours. The engine sounded perfect and in the garage they said the engine would pass the water glass test it was running so smoothly. I checked the water before I left and it was on the maximum line however on starting the engine after the MOT it was firing on three cylinders with smoke coming from the exhaust. This problem cleared although there was still smoke but I was able to recover the car back home without over heating. The engine management light was lit and on checking the 2 codes it was engine misfire and engine misfire due to fuel starvation. The cooling system took 3 quarters of a litre of water to bring the level back to the maximum line.
I have checked the oil which shows signs of water mixed in with it but there are no signs of oil in the cooling system. The tops of the pistons are dry when looking though the plug holes and the plugs them selves showed no signs of water. I am not entirely convinced that the problem is due to a hgf again because of the amount of water lose in such a short period of time, and the history of the car shows that there was an unexplained water lose before I bought it. I locked the engine flywheel before removing the head so there was no movement of the liners while I was working on the engine, and I also checked the liners for possible cracks and as far as I could see there were none.
My question is has anybody had the same problem and found it was caused by something other than the head gasket. I have a feeling that it could be that the turbo was damaged before I commenced work and perhaps the seals have perished allowing water to pass from the water cooling in the turbo to the oil passages but I am unsure. I also checked to see if there was any signs of coolant lose around the engine but found none at all.
Any suggestions would be most appreciated as I am at a loss to what it could be.
Regards and many thanks Marty

edit: Tuesday 21 July, I have now drained the coolant and oil and found no trace of cross contamination in either.:duh:

[wullie480]

Was the inlet manifold gasket changed as well?
This is a common weak point.

[martyw]

Was the inlet manifold gasket changed as well?
This is a common weak point.
Thanks for your reply, yes all the gaskets were changed and torqued to the correct poundage. I am very concerned with the amount of coolant lost in such a short period of time with out any outward signs on the cylinder block or driveway
Regards Marty

[DMGRS]

Which kit was used? The MLS and Payen BW750 gaskets have different failure modes, so knowing which will help diagnose. :)

[martyw]

Which kit was used? The MLS and Payen BW750 gaskets have different failure modes, so knowing which will help diagnose. :)

Thanks for the reply, I was in two minds which type to use, the one on the car was an MLS type but it fell to pieces when I removed it. So I elected to go for the single layer silicone type after checking the liner height of each cylinder and replace with new stretch bolts. Perhaps I should have refitted an MLS gasket and gone for a better brand, but I still don't understand how there could be such a large amount of fluid loss in such a short period of time.
Regards Marty

[T-Cut]

If the car was being driven when the head gasket failed, oil emulsification might have rapidly put paid to the turbocharger. It's only a bronze bush bearing and must have a good supply of engine oil. Any water mixed with it will be enough to ruin the turbo. The symptoms you describe could equally apply to several causes, but having looked at the others, I'd suggest looking at the turbo. It's easy to check by removing the large bore hose that goes to the throttle body. If there's any trace of oily water in there, you'll need a new turbo unit. While the hose is off, check for any slop on the compressor fan. If you can feel it waggling, the bearing is shot.

TC

[martyw]

If the car was being driven when the head gasket failed, oil emulsification might have rapidly put paid to the turbocharger. It's only a bronze bush bearing and must have a good supply of engine oil. Any water mixed with it will be enough to ruin the turbo. The symptoms you describe could equally apply to several causes, but having looked at the others, I'd suggest looking at the turbo. It's easy to check by removing the large bore hose that goes to the throttle body. If there's any trace of oily water in there, you'll need a new turbo unit. While the hose is off, check for any slop on the compressor fan. If you can feel it waggling, the bearing is shot.

TC
Thank you for your reply, I will check the turbo tomorrow.
Regards Marty

[T-Cut]

To check for turbo shaft slop, you have to remove the large inlet hose that comes up from the intercooler. But if you find water/oil in the upper, outlet hose you'll know it's failed.

TC

[DMGRS]

Thanks for the reply, I was in two minds which type to use, the one on the car was an MLS type but it fell to pieces when I removed it. So I elected to go for the single layer silicone type after checking the liner height of each cylinder and replace with new stretch bolts. Perhaps I should have refitted an MLS gasket and gone for a better brand, but I still don't understand how there could be such a large amount of fluid loss in such a short period of time.
Regards Marty

That's good to know - the elastomer gasket is a fairly solid item (the new revisions anyway, as long as it's a genuine Payen and not eBay tat).
The elastomer gasket usually fails oil-to-water (and vice versa) so that'll be where the water is going, if that's the problem.

[kaiser]

If there is water loss internally, there are a few ways that can happen.

Headgasket.
Inlet manifold gasket.
Crack in head, block or liner
Liner seal at the bottom compromised.

The engine light indicates it finds its way into a cylinder, and you have misfire,

I think we can thus safely ignore faults in the cooling systems and outside leaks as the main cause.

I would pressurize the cooling system to gain more information.

I would also just like to stress, that the standard torquing of the head gasket will give too low values, and that water loss can easily come from that.

And, worry about all the other add-ons discussed only when you have found
the root cause of your problems.

I include a link.
http://www.the75andztclub.co.uk/forum/showthread.php?t=214880

of special interest note the torque procedure discussed in post #34.

[martyw]

Hi, just to keep you up to date with progress. This morning I drained all the coolant from the system and found it completely clean. Next I drained the oil and was surprised to see that there was no emulsification in fact it was as clear has when I replaced it, so that would suggest that the coolant is escaping somewhere else, god knows what I was seeing last night.
I removed battery, air box and as many hoses as I could and checked the turbo shaft, there was a little oil visible on the air inlet side but not excessive. The air outlet was clean and so was the hose however on checking the turbo shaft I found what seems like about 3mm of play on the shaft. I now intend to remove the turbo and check internally for crystallization of the coolant because the cartridge will need to be changed anyway because of the play in the bearing.
More later Regards Marty

[martyw]

If there is water loss internally, there are a few ways that can happen.

Headgasket.
Inlet manifold gasket.
Crack in head, block or liner
Liner seal at the bottom compromised.

The engine light indicates it finds its way into a cylinder, and you have misfire,

I think we can thus safely ignore faults in the cooling systems and outside leaks as the main cause.

I would pressurize the cooling system to gain more information.

I would also just like to stress, that the standard torquing of the head gasket will give too low values, and that water loss can easily come from that.

And, worry about all the other add-ons discussed only when you have found
the root cause of your problems.

I include a link.
http://www.the75andztclub.co.uk/forum/showthread.php?t=214880

of special interest note the torque procedure discussed in post #34.

Hi, I actually used you article for tightening the head bolts, I found it when searching the forum for information on changing the head gasket on this particular model. I found that each bolt required re torquing three times before I was satisfied that they where all at the same. So I thank you for that information.
Regards Marty

[kaiser]

Hi, I actually used you article for tightening the head bolts, I found it when searching the forum for information on changing the head gasket on this particular model. I found that each bolt required re torquing three times before I was satisfied that they where all at the same. So I thank you for that information.
Regards Marty

My, my. Somebody actually listens!!:D
Nice to know.

BTW, if you want to see if you are loosing water inside the engine, check the oil filler cap! If the engine is hot, and you still have water and or emulsified oil inside the cap, water is getting in there, somehow.

If you have not filled the coolant system properly, it is possible that there could have been trapped air behind the thermostat. That would show as a loss of coolant, once the engine gets hot and the thermostat opens. However, once filled, that should not re-occur.

If that is the case, then the misfire could be lack of fuel (filter housing? becoming separated, regular occurrence) OR a problem with spark.
If, you have water in the one cylinder, it should also be possible to see on the plug itself, it should have a different colour to the remaining plugs.

This is a conundrum, an enigma inside a riddle!;)
But we will get to the bottom of it!

[martyw]

Finished removing the turbo and is totally knackered, wiggle one side and the other side moves in the opposite direction, about 3mm movement. I am going to order a replacement cartridge tomorrow. I am still left puzzled to were the coolant is disappearing to, I am 99% positive it`s not going in to the sump because the oil is clean and clear. So that leaves one alternative as far as I can see and that`s through the turbo and down the exhaust. I think that would also fool the lamba and cause a fault similar to what I received.
Regards Marty

[T-Cut]

Finished removing the turbo and is totally knackered, wiggle one side and the other side moves in the opposite direction, about 3mm movement.

QED. The turbo was indeed damaged when the head gasket failed. HGF in the 1.8T can be a rather expensive problem for the unwitting driver.

It's unlikely you'll see any 'crystallised' antifreeze in there. It will appear very sooty, oily and wet. Replace the turbo or just the CHRA and I reckon you'll be fine.

I am going to order a replacement cartridge tomorrow.

Can recommend the UK manufactured Melett cartridge for about £170 (ebay) . It comes with a balance certificate and 12 months' warranty. But you must replace the oil feed pipe for this to apply.

I am still left puzzled to were the coolant is disappearing to, I am 99% positive its not going into the sump because the oil is clean and clear. So that leaves one alternative as far as I can see and that's through the turbo and down the exhaust. I think that would also fool the lamba and cause a fault similar to what I received.

Correct on each point I'd say. The slop in the shaft is an unrestricted exit for coolant and oil.
Lambdas don't like contact with with engine oil. Components in the oil can cause contamination of the 'element'. If the lambda continues to be a problem, it should be replaced.

TC

[martyw]

Hi,
thanks for your replies and advice. I am considering, while the engine is stripped down, double checking the head gasket and changing it from the single layer to the MLS type as fitted when I purchased the vehicle, but a better quality one. I would hate to get it all back together and have the same problem happen again. Besides that I have to go in to hospital next Wednesday for an operation on my ribs so it will be sometime before I will be able to get back to working on the car.
I will let you know how the repairs go and the outcome.
Regards Marty

[minimutly]

How exactly does coolant get through the jacket/seals in a turbo?

[T-Cut]

How exactly does coolant get through the jacket/seals in a turbo?

It can't. I really don't know why I said it could.

TC

[T-Cut]

So there are shaft seals on the coolant side as well? I thought a worn shaft/bush bearing might allow coolant to bleed into the exhaust system, but had second thoughts after looking at the central casting. Isn't the coolant jacket isolated from everything? Just a cavity cast around the bearing housing? Having said that, the turbo I repaired was definitely wet as well as oily. Of course turbos are ruined when coolant gets into the engine oil via a failure in the head gasket. So that may well be the origin of the water seen in a failed turbo. ??

TC

[T-Cut]

3mm play is HUGE. It will surely allow oil and/or coolant to pass into the inlet or exhaust systems. Both coolant and oil will be at high pressure in a running engine..

Yes the oil feed to the turbo bearing is at full running pressure, but how so the coolant? How does the coolant get inside the compressor housing? As I saw it, there's no route for the coolant to take.

TC

[martyw]

Hi,
I talked to the turbo cassette manufacture this morning and although he couldn`t give a definite answer, he said there was a probability that coolant may have been ejected from the turbo in to the exhaust depending on the amount of damage caused to the internals ie cracks to the cast due to heat and movement from the worn bearing. Unfortunately I dont know how long the engine was run with the turbo in this condition, I do know however that in the vehicles history going back to early 2014 that there was an unexplained coolant loss because I have the garage receipt for the work carried out. The receipt is for changing the inlet manifold gasket but the work sheet is worded unexplained water loss. I think I will just carry on and complete my repairs, I have decided to change the head gasket back to a MLS, using a Victor Reinz gasket. I have ordered a new cassette for the turbo and I will fit that when it arrives. I intend to keep the car for at least 3 or 4 years unless I find a MG ZT 190 before that, but I am one of those people that wont be able to settle and enjoy the car knowing that I may have missed something.
Thanks for all your help Regards Marty

[minimutly]

irespective of whether the turbo is causing your issue, it needs fixing.
Personally i think its unlikely, and almost impossible, other than a cracked turbo housing theres no way it could happen.
I suspect your water "loss" was air being evacuated, who knows about the missfire.
However, i'm prepared to be proved wrong.

[martyw]

irespective of whether the turbo is causing your issue, it needs fixing.
Personally i think its unlikely, and almost impossible, other than a cracked turbo housing theres no way it could happen.
I suspect your water "loss" was air being evacuated, who knows about the missfire.
However, i'm prepared to be proved wrong.

Hi, it is a mystery, the 1.8 turbo is supposed to take 6.2 litres of coolant according to the information notice on the bonnet shut panel. This has taken 7 litres after bleeding and then another .75 litre on Monday. I also have a Rover 75 2.5 V6 and replaced the coolant last year on this car so I do have experience with the bleeding of these systems. God knows where the coolant went, it wasn't lost through air evacuation because I ensured that all the air was released from the system before taking the car out on the road and then checking the level before several engine runs to operating temp before the MOT.
The problem is a long running one according to history of the car, so only when all the repairs are completed will I know if changing the turbo cures the problem.
Regards Marty

[martyw]

I just wanted to make it clear that the bleeding of the system was completed properly. I have been working on the car over several months to give me something to do has a hobby after my forced early retirement due to rib damage, so everything I have done on the car has been checked and then checked again. The only thing I didn't check was the turbo and that was only because the history shows it was fitted with a new one 3 years ago, or should I say the last owner was charged for a new one.
You live and learn, actually while I think about it I took an handful of the exhaust fumes when I returned home which was light grey in colour and it didnt smell like oil. Thats why the first thing I did was check the piston tops and plugs to see if any of them showed signs of water, which they didnt, if any thing the mixture looked to rich ie sooting. The emissions readings were perfect on the MOT.:duh: I love working on cars, I have done it for most of my life and I am now 60, I like to think that I have come across most problems and been able to sort them my self. However there's always that one problem that shows it self and you are unsure what to do about it. That is where this and other forums are a god send, answers are only a question away.
Regards Marty

[martyw]

Sorry about the late update to this problem due to my OP. I decided to change the head gasket as well as the turbo cassette in the end. On removing the head I had some how managed to miss a small water chase on the head right over the fire ring on cylinder three. The water chase was no more than 7.5mm long and resembled a very small scratch, but you could see where the coolant had been released in to the cylinder. I had the head pressure tested and then skimmed by 8 thou to remove the chase and then I refitted the head using a Victor Reinz MLS gasket.
I changed the turbo cassette and all seems to be fine now although the car as only travelled 42 miles. Thanks for your help and suggestions.
Regards Marty