Cadillac Repair: 93 CADILLAC SEVILLE 4.9L, blown head gasket, oil filler cap

Question
I have oil in the water. I have pressure checked the oil cooler and cannot find it leaking into the coolant side of the radiatior. I have torn the engine down to removing the intake manifold and the gaskets do not show leaks.
Where else can an oil leak under pressure get into the coolant? I don't feel like it is a blown head gasket.
Thanks you for your time.


Answer
Hi Phil, Leak places with this engine that will allow anti-freeze into the oil are from a cracked intake manifold gasket by the end coolant passage or past a head gasket because of bad head bolt threads stripping out in the block. When this happens the oil turns to a cosistancy of pancake batter and if you remove the oil filler cap you will see build-up on the backside. Oil that gets into the coolant could be from a bad oil cooler inside the raditor. I suppose if you had a cracked block oil could also get into the coolant passage. I had one that the block was porous and oil leaked out through the back of the block between the engine and trans so it looked like a rear main seal that was bad. If the crack was next to a water jacket then the oil would have gone into the coolant instead. Sorry I can't be more help. Good luck. Bill