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Tim
 
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Default Rats! Burned exhaust valves in my 140!

Took my boat out to the lake Sat. and I noticed the 140 Mercruiser was
running a little bit rough. only at idle,a nd didn't want to start very
well. Still after warm up a bit, it took off doing good. throttle up,
and planed out nicely. ran smooth at 3200 RPM. Ok later my brother said
I had low compression on a cylinder and suggested we run a compression
test. 1-125 lb. 2-80 lb. 3-80 lb. and 4-50lb! CRAP! No sign of water
on the dipstick, but took off the fill cap and it was milky white.
CRAP! Pulled the head and #4 ehxaust valve was burnt pretty badly and
looked like crossfiring between #2 and 3.

SO....to the performance shop it goes, to see if it's cracked, will
pass a flow test, have new high temp valves installed and planed, and
get some new headbolts due to possible streaching.

OK, I've heard pro's and cons concerning using Mercruiser steel head
gaskets. Fel-Pro makes a great head gasket, which is your basic copper
"sandwich" whis has been a really good gasket for automotive use for
years. and some say that is the way to go.

Others say to use only the OE or OE style steel gasket. What would the
the advantage (if there is one) to using the steel gasket ? I can
understand not using the copper alloy in salt water, but this boat will
never hit the salt.

Any suggestions?


Tim