JohnK944T

Alright, I have owned the car 2 weeks and have tried to check everything out. I am not sure what to think. The coolant was low, I added a liter and bled the system. The level remains the same after 100+ miles. My oil filler cap had foam in it, and about 2" down into the tube there was foam. Cleaned it and it has not come back. Noting on the did dip stick... No foam, no water. Finally, I may be seeing things, but the expansion tank looks like it goes from green to dark line, to foam. The head should be good, done in the last 5k miles. I run 16 psi.. The mechinic says just condensation? It has been hot, 85± 3 degrees humidity is up. Should I drain the oil and look closer or what??? Thaks, JohnK

IceShark

Would find it really hard to believe it is condensation unless you are parking the car in a freezer.

I'd look closer and think head, especially since it was recently done and you are running higher boost. Oil tests are pretty cheap these days, pull some and get it tested. Expansion tank could be remants of old problem as they are tough to clean out. Maybe take it off and do a steam clean on it?

Perry 951

IMPORTANT! What car / year? What else did they do when the head was done.. and when is the last time the cooling system was flushed? You could try that and see what comes up. I'd just filler up with water for a few weeks and see if any oil spooges up into the tank. Let us know the info and we can see if there is a solution.

[ 06-27-2001: Message edited by: perry951 ]

TomH

Sounds like your mixing to me. It usually not the head, its the oil cooler seals. What color is your expansion tank? Is it white plastic, or already stained yellow from previous mixing?

fletch.

I don't think condensation is accurate. Soulds like head gasket to me. I have seen 5 oil water mixes, and all 5 have turned out to be the head gasket. There are other causes, but going with the odds it sounds like head gasket failure.

JohnK944T

The details on the car are as follows;
1986 944 T, 90k miles
White expansion tank/ 6 months old
Valve job, wide fire HG, raceware studs/ 4 months. K27DR turbo & Huntly MAF III/ 4 months

Perf. is great.
Not sure on the coolant flush, but Waterpump was done 4/11/00.

I will drain oil next week and take a look, How about the oil/water cooler? What is the story on that and is there any way to root cause a leak there?

Thanks,
JohnK

TomH

Mixing is a common problem when the oil cooler seals fail. Age seems to be the biggest factor, as its bound to happen to any 944 eventually.

All you can do is replace the seals, which should hold you for another 10 years, so I've read

keith

TOM H:

1- 951s don't have the cooler seals problem like the 944s do (oil cooler is removed from engine, and not water cooled).

2- expansion tanks turn yellow, brittle, and crack from exposure to HEAT over the years, not necessarily oil. The dingy yellow resevoir isn't a good sign of anything, really...

Saw these items in a previous post, so I thought I'd clear it up

chuck951

>>>>1- 951s don't have the cooler seals problem like the 944s do (oil cooler is removed from engine, and not water cooled).

I sure hope this is bad information as I just paid my wrench to replace my oil cooler seals in my 86 951!

keith

right - the 944 has an oil cooler which is mounted on the side of the block, under the (and part of)the oil filter assembly. It is surrounded by a jacket of coolant. The seals here will get brittle with age and leak, allowing the oil (higher pressure) to flow into the coolant (lower pressure)

On a 951, instead of a housing containing the oil cooler, the oil filter mounting block has more or less a flat plate with outlets for the oil lines to and from the EXTERNAL oil cooler (up front beside radiator, in front of passenger tire). i am at work right now, and can't verify, but your mechanic may have replaced seals at block or at cooler, depending on what and where the seals are in that situation... I don't recall offhand if there is a redundant use of the 944 style oil cooler seals in the 951 setup, but this could not be a source of oil/water mixing like in the NAs....

If you are concerned about the trustworthiness of your mechanic, give me the part numbers of the seals from your invoice and I will verify that they are indeed items related to the 951...

IceShark

Chuck, it isn't exactly bad information, but is somewhat misleading. The turbos don't have the old internal water to oil heat exchanger core & seals, which ALWAYS failed. But they still have the same housing with a pipe type fitting with O rings and seals replacing the heat exchanger core.

This new arangement is far less likely to fail, but it can still fail (especially since those seals are now getting pretty old if original). So when there is intermixing people usually start to think head gasket blown from boost rather than the automatic "oil cooler seals".

Dan

keith

DIFFERENT housing.

Just checked PET, and yes, there is an O-ring seal there, on the 951.

Irregardless, the oil/water mixing at the oil cooler issue is not a 951 issue.

Can it happen? Possibly, I couldn't rule it out with out having anothere look at the location of the water passages in relation to the oil passage and the design of the inside of the plate on the oil filter mount.

However, if this is the cause of the mixing situation on 98% of 951s out there, I'll eat my shoe.

Actually, I'll eat them both!

what is MISLEADING is confusing the common 944na oil mixing issue with a 951 problem...

Cheers!

MadMax

What about the S2. Does it have the same type of oil cooler as the NA's or is it like the Turbo's? I haven't looked for the oil cooler on my S2 but you guys have got me thinking now.

Regards,
Max

Tabor

The S2 and 968 use the Turbo style cooler.

As always, don't risk your life on my knowledge.

fletch.

I have heard but not experience a turbo oil water mix. Not sure how it could be possible, but I have seen posts about it.

The reality of this situation is that the oil cooler is remote and has a totally different housing from the N/A. Oil water mix on a turbo is a head gasket in every case I have seen.