Advice please before I torch the car

[avante101]

Hi,
I have a Celebration 944 (1987, 2.5n/a, 8v, 120k m) that has a problem that has the garage I am using and me stumped. Any advice would be gratefully received.
The low oil level warning light came on and on investigation the oil had mixed with the coolant. As the car runs well and shows no other sign of a head gasket failure we changed the oil cooler seals with genuine Porsche parts. After about a day the oil was back in the coolant. A reconditioned oil cooler was sourced from D9 and fitted with new seals, but the oil is still getting into the coolant.
The mechanic at the garage I am using is competent and knows his way around old Porsches (he has a 924 and 911) so I don't think he is doing something wrong.
It's really frustrating as the car is in otherwise show condition and starts and runs perfectly.
Can the oil and water mix somewhere else? Could there be no other symptoms from a head gasket failure?
Any advice please?
Thanks.

 

[944 man]

Perhaps the fluids are mixing through cracked galleries?

 

[zcacogp]

Is it possible that the head gasket has failed between a coolant passage and an oil gallery, but not anywhere else? (i.e. The seal around the top of the cylinders is still intact, where the gasket is reinforced.)

Old gasket, may have deteriorated over time.


Oli.

 

[ChasR]

I'm afraid I'd have to go with Simon's and Oli's diagnosis.

 

[avante101]

Thanks. I think I will ask the garage to take the head off and change the gasket. I am clutching at straws a bit now - I only bought it about 6wks ago and have driven about 20miles in it! Changed the belts as well before all this started!

 

[zcacogp]

Don't take my comment as being reliable - it's a guess, from a ham0fisted amateur, nothing more.

I hope you find the problem, whatever it is. In terms of £/mile, it'll start to look like a very expensive car pretty soon. And (unfortunately) quite a lot of the work for changing the head gasket is the same as for changing the belts ...


Oli.

 

[Hilux]

N/A cars prior to the S2 have a water/oil heat exchanger that can break down and allow the two to mix.

See here for details.......................

If all other possibilities have been looked at then there`s your problem.

 

[zcacogp]

Paul,

I'm assuming that's what the OP referred to when he spoke of an 'Oil Cooler'.


Oli.

 

[Mike_Pollock]

Does the oil get in to the water?
The oil is under much more pressure than the water when its running, so I would be looking for a "gravity" way for the water to get into the oil, in which case the oil cooler gasket must be favourite.
When I changed the gasket on mine, I tried to take a couple of shortcuts and although the seals I replaced, worked well, water had got into the sump as I was removing the cooler unit.
I would change the oil and filter first - just to eliminate the possibility - and its a lot cheaper than taking the head off!
Hope that helps
Mike
PS - Dont torch it!

 

[Hilux]

Paul,

I'm assuming that's what the OP referred to when he spoke of an 'Oil Cooler'.

Be careful regarding the term as S2`s and Turbos have a seperate oil cooler. I was referring to the oil water heat exchanger mounted on the engine on earlier N/A cars.

 

[zcacogp]

Paul,

Ah. OK. Thanks for the clarification.

To be honest, I haven't thought about it. I seem to recall seeing an oil-to-air cooler on my S2 somewhere in the front bumper (offside, low down - non?) and had heard about oil-to-water coolers on cars, but had never really pondered it.

Is that the difference then? S2's and turbos have oil-to-air coolers and other models have oil-to-water coolers?


Oli.

 

[Hilux]

Is that the difference then? S2's and turbos have oil-to-air coolers and other models have oil-to-water coolers?

The pre S2 cars have an oil water heat exchanger much as per early VW engines where the water system extracted heat (allowed heat transfer) from the oil system to aid cooling.

The S2`s and Turbos have a front mounted oil cooler which utilises air flow to cool oil via a matrix.

 

[zcacogp]

Paul,

Thanks.

Actually, the early Golf GTi's (1800 Mk1's, for sure) had a front mounted oil cooler (using your terminology) - cooling the oil to air. It was mounted by the radiator. Later cars (Mk2's) had a heat exchanger (oil-to-water cooler) which sat on top of the oil filter. The advantage of the heat exchanger is that it allowed the engine to warm up more quickly as there was no oil cooling until the radiator thermostat opened. With the Mk1's, the oil was cooled all the time, even when the engine was cold.


Oli.

 

[Hilux]

Correct []

 

[944 man]

I presumed that the OP was referring to the oil/water heat exchanger, when he said that seals had been changed.

 

[avante101]

Just a thought, but how much oil is apparent in the water now? Once oil gets in the water and is distributed around the cooling system, radiator, heater matrix and everything, it can take some getting out. If the oil/water heat exchanger seals were faulty and have been changed, even with flushing you could still see blobs of oil appearing in the header tank for a while - so unless the oil level is still dropping and there's lots of oil in the water, it might be worth flushing the system again, waiting a while, flushing again etc.?

 

[jr2015]

before stripping the head why not pressure test the system? you might even be able to get some visual clues to where the problem lies in the form of bubbles and drips.
jr

 

[zcacogp]

Depends which way 'Up' is.

Heat exchanger sat between the oil filter and the filter housing, but the filter hung down (unlike on the 944 where it points up).


Oli.

 

[ChasR]

I was about to suggest that considering that you can changed your heat exhanger (I assume) and your seals, that the next port of call could be to get a leakdown test done on the car. If this checks out fine, it's probably worth checking out the oil/coolant and flushing it out once more.