A badly scored bore in a 1983 evinrude 50

[metcalfej]

From a combination of fiddling without knowledge and forgetfulness we have ended up with a burnt piston and a badly scored bore, in one of the two cylinders, the really cutting thing is that the rest of the engine is perfect, the top cylinder has 150PSI.
Qu 1. Is it possible to rebore the engine and to what size do you re bore it?
Qu 2. can this be done by a motor vehicle engine reconditioner or does it have to be done by a marine specialist?
Qu 3. Where can over sized pistons and rings be found
Qu 4. Is it worth it?
I have a seloc manual for the engine but it doesn't give you any guidance on this
Thanks for you advice
James

 

[F_R]

Re: A badly scored bore in a 1983 evinrude 50

1. Yes. Bore to the minimum size required to clean it up
2. Yes, if he's good and has the equipment. Ask first.
3. Your friendly Evinrude or Johnson dealer. If it turns out that they are no longer available, try Sea Way Marine in WA. They have a website. Google them.
4. You decide.
5. Don't they sell powerheads here at iboats?

 

[Dhadley]

Re: A badly scored bore in a 1983 evinrude 50

It can indeed be bored. I would strongly suggest having a marine machine shop do the boring. Oversize pistons are available both from Bombardier and aftermarket companies like Wiseco and Sierra. Most, if not all, the parts you need can be found here at iboats.

I'm not sure about machine shops over there but most here that bore marine blocks can supply the pistons. As for the sizes, check here and at www.wiseco.com for your choices.

If the rest of the motor is in that good of shape I would guess that it's well worth doing. Only you can answer that.