Oil in my antifreeze?

[blue62]

Originally Posted by 1Madmachinist

So I'm still waiting on some parts so this weekend was a bust for trying to diagnose/fix anything intermix related. The day I posted this I pulled a sample out if the expansion tank and skimmed off what little bit of oil was in there. The coolant looks old but not terrible and none of the hoses look to be swollen or overly soft for being 20 years old. I have driven it everyday since back and forth to work and to run errands etc. The oil and coolant levels haven't changed and there seems to be no extra oil in the coolant only light swirls floating on the top and the oil dipstick still shows no signs of coolant contamination. Temps here have been in the 90's all week but the temp gauge always stayed between the 180 and next hash mark on the gauge (235?) even sitting in traffic. Also I haven't seen any white or black smoke from the exhaust. I guess none of that means the head is not cracked just trying to remain positive.
I have contacted the previous owner and if anything he is oblivious to the problem. To get the car ready to sell he had the oil changed, the plugs replaced, and a new top put on by the same local mechanic who he gave me the information for. He also gave me the contact information for the person he bought it from (I believe they both belong to the same car club which he urged me to join) so I don't get the feeling he is trying to get over on me.
I find the navigation thing interesting. The PCM and Nav unit are all Porsche parts and the car came with all the needed literature and extra map discs. Also it has the 662 option code listed on the sticker under the hood and in the maintenance booklet. Maybe it's a later year model? If the maps were up to date it would still work properly as the GPS still works.
Kinda the least of my worries right now though.

You could do a coolant system pressure test.
You can get a coolant system pressure testing kit at Harbor Freight at a reasonable price. Such a test should tell you if you have a cracked head adjacent to a coolant passage or not.

You could also test the coolant for the presence of hydrocarbons if present that would indicate a blow head gasket or cracked head adjacent to a coolant passage. the little tester for this used to be in most auto parts store.
Have not seen one in a few years but also wasn't looking for one.

Both mentioned tests are very simple and easy to do.

The coolant tank cap and the oil fill cap are very close to each other so there is a possibility that when the oil was changed the person changing the oil poured a small amount of oil into the coolant tank by mistake. Things happen.
I have come very close to doing this myself several times

[tonythetiger]

Originally Posted by blue62

Y

The coolant tank cap and the oil fill cap are very close to each other so there is a possibility that when the oil was changed the person changing the oil poured a small amount of oil into the coolant tank by mistake. Things happen.
I have come very close to doing this myself several times

my thoughts and hopes as well. hope this is just a little cross-contamination so your first experience with the M96 is a good one. I would flush the coolant and observe.
best to you.

[1Madmachinist]

So I dumped the oil an no signs of coolant. Dumped the coolant and after sitting for more than 24 hours there is no oil floating on top so I am assuming there's very little in there. I pulled the thermostat and the water pump and it looks like the water pump has either been off before or it has been changed because the gasket has already been cut. It has a plastic impeller (still intact) so I am changing it and the thermostat while I am in there. No apparent oil in any of these cavities.
I pulled the oil cooler off and the O-rings were completely flat and two opposing o-rings, an oil and a coolant port, were crumbly but not falling apart. Looked like an oil streak in between those ports but honestly that could have happened when I pulled it off.
So the flushing will begin and we'll see if the oil returns.
My question is the o-rings I ordered seem pretty loose in the trepan grooves in the top of the motor.
I have 2 PN 99970740940 26X3mm and 2 PN 99970738940 35X4mm and now I see a third size listed as well. Are those the correct o-rings?
Thought I saw another post with these part numbers listed as well.
Thanks,