Oil cooler seals or headgasket here

[plyhammer]

[9FF]

Depends if that came from the oil pan or the coolant tank. Generally, coolant milkshake is from a bad oil cooler seal, oil milkshake is from a bad head gasket.

[plyhammer]

Oil pan

[plyhammer]

I guess sons birthday present will wait another week or two

[9FF]

Originally Posted by plyhammer

Oil pan

Originally Posted by plyhammer

I guess sons birthday present will wait another week or two

That's disappointing but fortunate that it didn't happen while your son was driving. He might have continued to drive it and wrecked the engine.

Coolant in oil: replace head gasket and rod bearings, use first oil fill as a flush, drain and refill with new oil.

Oil in coolant: replace seals, use water hose to flush coolant system and reverse flush radiator, refill with new coolant/distilled water mix.

[plyhammer]

Yep What I thought. Thanks for confirming

[plyhammer]

Prolly best to do it all while I'm on it

[944 Ecology]

Use a leakdown tester to eliminate/confirm head gasket failure. A bad headgasket will show up as bubbles in the overflow tank.

[Pauld_94S2]

Mark,

FYI, coolant in the oil can still be a bad seal in the oil cooler, just not as likely.
Do the leakdown test first.

[dgcantrell]

Yep. Definitely do the leak down test first.

[wrench1]

Hammer,
Do the leak down test first to see if you truly have a blown head gasket.

But, have you thought about the oil cooler itself? If the cooler itself has a leak (hole or crack) once the engine shuts down the oil pressure drops to zero and the pressure in the cooling system will work its way into the oil, instant milkshake.

If you found this quick enough you might not need to pull the oil pan for rod bearings. My oldest sons cooler failed in his 88-944. Replaced the core and took a chance. We won the gamble and he is still driving three years latter with oil pressure between 3 and 4 bars hot.

Good luck with the car but check the core to be sure.