I've seen them crack in the heads or block or both. Inside and out. Boat
motors have pretty low water pressure so it might take a while to notice. A
small leak could just get evaporated by the engine oil heat. If it gets
below freezing and you keep your boat outside you need to drain it. Is not
worth the risk not to.

"bob" wrote in message
...
For those of you who have seen a Chevy 350 (1992 vintage) crack from
freezing,
is it common for the heads to crack and not the block? Does the block
usually
crack without cracking the heads or is the entire engine usually trash
(block
and heads cracked)? Can it freeze and take months for the cracks to get
big
enough to cause a problem? When a chevy 350 block freezes, where does it
usually crack? (in the lifter valley, in lower end or to the outside).

The story (been mostly posted before)

I've been trying to figure out what happened to the boat motor. Both
heads
cracked. Both cracked to ourside and 1 had cracks in 2 of the combustion
chambers. The 2 different guys who inspected the heads both said "looks
like
it froze". The 2 combustion chamber cracks were on the same side on the
low
end so water would drain from there last. The problem showed up (water in
oil,
hydrolocked with water in pistons 5 & 7) in late July in Texas after
putting
many hours on it since "winter" (we had a mild winter last year and even
if I
forgot to drain it, I don't think it got cold enough to freeze under the
boat
cover, under the padded motor cover). I did overheat it last summer and
warped heads (water in oil and hydrolocked). No cracks found in heads
then.
Had them planed and rebuilt. No problems the end of last summer nor
beginning
of this summer.

Anyway, new heads appears to have fixed it but still wondering how I
messed up
and broke it. Just wondering if I should be concerned about a crack
opening up
on the block.

Thanks again for any insight.
Bob
bbusselman at hotmail dot com