Hi,
I found a hairline crack going from front to back down the middle of the head on this car a month ago. It has 177K on it. I don't know how long the crack has been there.
When cold, I could see a tiny trickle of green antifreeze oozing out of one part of the crack . When hot, the crack has some oil clinging to it, but no evidence of antifreeze. I assume it only leaks when cold.
The car currently has very low oil pressure, and goes down to zero when hot and idling.
The car was consuming about a pint of coolant every 50 miles for about a year. Must have been burning it. I put a cooling system sealer in, and the coolant consumption has dropped to a pint every 300 miles. Never any smoke or steam from the exhaust. Pressure test of cooling system when warm revealed no leak. Didn't test it cold.
The oil has never exhibited the clasic "white slime" look of oil/ af mixing. But over years could this trickle of antifreeze into the oil when cold ruin an engine, with regular 5k to 7k oil changes???
Thanks