Squirt about 1oz of 30 to 50 wt oil in that cylinder, enough to wet the
entire circumference and check compression again. If there's no change it
should be a valve or gasket. If the compression jumps up it may be a
piston/ring which means you need to go into the block. The only other
possibility is that a hole in the piston is large enough that the oil won't
seal. In that case you might be able to see it with an inspection mirror
and a small flashlight through the spark plug hole.
LD

"nate" wrote in message
. ..
I have a 8 cylinder 350 (I think GM..it's in a boat)

Engine back fires and sputters. Engine does not leak oil that I know of.
(or at least not very much)Compression test revealed 0 compression in 1
cylinder and all others were ok. Based off these symptoms, Is it likely
that I will have to do work on the engine block or will the problem be
likely in the Head (gaskets or other)