Rebuild question 06 johnson 90hp

[Charlestonkey]

Just bought a 06 Johnson 90hp 2 stroke 60 degree that ran hot after the thermostat got stuck. I'm assuming a total rebuild will be needed but am wondering if only 1 cylinder was affected and it has low hours, is it necessary to replace all the other pistons? Just a preliminary diagnosis, after pulling all the plugs, only the 1 was fried. Thanks.

 

[jonesg]

Re: Rebuild question 06 johnson 90hp

One piston rebuilds are acceptable per the factory manual, but it depends on the extent of the damage obviously.
The head is probably warped, that can be fixed easily.

If you commit to doing it, strip the powerhead and have the block measured at a marine machine shop to see if its still in spec.
They usually charge $125-150 around here per cylinder for machine work.

I'd check that carb on the bad piston too...real closely.