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