I just checked my engine cylinder compression and want to know if this is good compression or so-so and how long till I may need a rebuid. The motor runs just fine just curious. I have a 460 the #'s are as follows 1-120 2-140 3-130 4-135 5-125 6-130 7-130 8-130 I checked them all twice and this was the highest # for each cylinder, also hooked up a manual oil pressure gauge and am getting 55psi at idle. Any help would be appreciated!

For the heck of it try a can of that "restore" I got a buddy that swears by it. It's supposed to raise and even out your compression.

I just checked my engine cylinder compression and want to know if this is good compression or so-so and how long till I may need a rebuid. The motor runs just fine just curious. I have a 460 the #'s are as follows 1-120 2-140 3-130 4-135 5-125 6-130 7-130 8-130 I checked them all twice and this was the highest # for each cylinder, also hooked up a manual oil pressure gauge and am getting 55psi at idle. Any help would be appreciated!

If this is a standard 460 Marine engine, then your compression ratio is about 7.7:1 and so I'd say your cylinder pressure is almost perfect and damn-near dead even, taking varying valve timing events into account. Keep changing the oil and plugs and run it for another 30 years.

LO