I think my motor is shot

[imported_stump jumper]

I recently purchased a boat with an evinrude outboard. I think the motor is a looper and the numbers between the cylinders are 115393M and 002015. The motor would not idle and ran very rough. The compression in the cylinders is 120, 60, 115, and 95. The mechanic said that the motor needs to be rebuilt. I do not know if I should rebuild the motor, without knowing the age. Any suggestions would be welcome. Also, I have a chance to buy an '89 or '90 200HP Mercury, any thoughts on this motor?

 

[WillyBWright]

Re: I think my motor is shot

Heck, it could be nothing more than blown head gaskets. Worth yanking the heads and having a look. 115393 is a 1973 115 crossflow.

 

[throwback2332]

Re: I think my motor is shot

If you just purchased it clean the carbs good and run some seafoam though it first.

 

[F_R]

Re: I think my motor is shot

Well Seafoam might free up some stuck rings, but 60 psi sounds like more than stuck rings to me. Pull that head and see what happened in there, and go from there.

 

[tashasdaddy]

Re: I think my motor is shot

don't right it off till you investigate, have you price a newer 115?

 

[imported_stump jumper]

Re: I think my motor is shot

I cleaned all 4 carbs thoroughly. The motor will not get near idle speed without dying. There is no evidence of water on the plug of the cylinder with the bad compression. Does this rule out a head gasket? Should the motor still idle even with the compression problem? Thanks so much for all of the help.

 

[F_R]

Re: I think my motor is shot

It may rule out a head gasket, but it does not rule out something busted, like a ring or bearing cage, that chewed up a piston and cylinder wall. Pull the dang head! You can see even more by pulling the bypass and exhaust covers.

 

[tashasdaddy]

Re: I think my motor is shot

don't run it any more, till you find out whats wrong. cleaning the carbs has nothing to do, with the compression.

 

[Chinewalker]

Re: I think my motor is shot

Your motor is a 1973 and is not a looper. It is commonly referred to as a crossflow.

Definitely pull the cylinder head and inspect the innards. Anything else you do at this point is wasting time/money until that is done...

- Scott

 

[imported_stump jumper]

Re: I think my motor is shot

Thanks guys, I will pull the head this evening