Compession bad

[69vette427]

Well the boat has been sitting for a few yrs. Took the plugs out spraied WD40 into cylinders. Took compression check.
#1 and #8 had 0 psi.. 4 others had about 100 psi. The other 2 had around 170. Not looking too good. Is there anything esle I should check before tearing it down?

 

[TimeZone]

Re: Compession bad

I would probably do a "wet" compression check. Put about a tablespoon of proper oil into the cylinders and try again. I like to use two cycle oil because it burns cleaner when you do get it going. If the compression goes up it's probably the rings or cylinder walls. If after adding the oil, the pressure does not go up, your valves may not be seating properly and that could be for a variety of reasons. If there is no pressure rise in only one cylinder, it could be because of a blown head gasket. 0 psi is not looking good though.

Good luck,
Ron

 

[69vette427]

Re: Compession bad

One more thing I pulled the plugs and cranked the engine and the was some rusty water that came out of number 6 cylinder

 

[Bondo]

Re: Compession bad

One more thing I pulled the plugs and cranked the engine and the was some rusty water that came out of number 6 cylinder

Ayuh,.... Guessin' this is a Saltwater boat,..??

I'd think yer motor is Junk,.... or possibly a rebuildable core...