1981 evinrude

[patmac]

I have a 1981 140 hp motor with one bad cylinder.
Can I replace just one piston? The other 3 have 125psi compression. My friend says thats the way to fix it. Looking for advice. Thanks for the help.

Patmac

[jjacobs007]

the cylinder is probally scored which would need boring out and then bigger piston,so keep things even no vibration its bad really bad to a outboard.you can probally do it yourself for like 600.00 for all 4 cylinders plus have more hp.

[emdsapmgr]

It is permissible to replace one piston or to overbore just one cylinder and put in one oversize piston. Personally, I'd prefer to match the piston with a Bombardier replacement. Also, you should at least hone the other three cyls and put in all (4) new ringsets. Any overhauled engine should also get a new water pump impeller, overhauled carbs and two new thermostats.

[patmac]

Thanks for the help. I guess I will do all four. I do have a new water pump to install when I rebuild it. I'll let you guys know how tihis turns out when I'm done.

Patmac