Stephen Trapani wrote in
:

Any ideas?

Stephen



I assume it has a heat exchanger, not raw water cooling. Fill the fresh
water side with coolant. Leave the cap off the fresh water heat exchanger.
Start the engine and idle it until it warms up a little, but not hot. A
little coolant will naturally escape as it expands. Watch the level with
the cap off. See any massive bubbling, indicating there are hot gasses
escaping from the cylinders into the cooling passages in the head and
cylinder walls? This'll tell you if the head is cracked or is warped
enough to let gasses bypass the head gasket into the cooling system. Not
rocket science, but reliable. No computer is necessary...(c;

Also, note if the engine runs smoother with the pressure cap off it.
Sometimes small quantities of pressurized coolant squeeze their way into
the cylinder as it sucks in fresh air, compress and EXPLODE INTO STEAM
inside the cylinder head as the piston comes up over TDC, making a bad
knocking sound, too! Are you losing coolant for no apparent reason? This
may be why if you are.

Flush out the bilge with fresh water after midnight when the greenies
aren't watching to get the little coolant out of the bilge...(c;

No fun....

--
Larry