Evinrude 3012 3hp lightwin

Looking to oversize piston and rings for my 1953 lightwin. Compression went last year, and I am taking apart to replace pistons rings, and bore head. Any idea where to find pistons and rings for this. Part numbers I have found on this site are obsolete with no supercede. Original bore is 1.562 dia. Is there a place to find a piston that is either original or can you buy one same diameter but oversized by .020? How does length of piston and pin for arm in relation to the piston come into play? Not really a big small gas engine guy so please excuse my ignorance, lol. More of a project to see if I can get it together and running than anything, seems like I don't have anything to lose as its shot if I don't find pistons and rings.

Thanks,
Doug

Re: Evinrude 3012 3hp lightwin

Try Seaway Marine they stock NOS (New Old Stock) parts.

Sea-Way Marine-your source for Marine Parts - Johnson Outboards, Evinrude Outboards, Chrysler Outboards, Mercury Outboards, OMC & Merc Cruiser Sterndrives

0277283 ! PISTON ASSEMBLY,Less rings .020 O.S.
Superseded by 0383240 ! PISTON .020 $58.00

0378412 zp RING SET $28.86

Re: Evinrude 3012 3hp lightwin

hidef said:

Try Seaway Marine they stock NOS (New Old Stock) parts.

Sea-Way Marine-your source for Marine Parts - Johnson Outboards, Evinrude Outboards, Chrysler Outboards, Mercury Outboards, OMC & Merc Cruiser Sterndrives

0277283 ! PISTON ASSEMBLY,Less rings .020 O.S.
Superseded by 0383240 ! PISTON .020 $58.00

0378412 zp RING SET $28.86

Click to expand...

Wow, thanks for the help. So if I wanted to do both pistons, its 2 assemblies and 2 ring sets correct? Also, in your opinion, is this worth it to spend $200 on these, buy all new gaskets and put back together, or should I just start looking for a new old motor?

Re: Evinrude 3012 3hp lightwin

You could probably get a new old motor for less. If you like this one, are attached to it, and enjoy working on old motors, then sure go ahead and do the work. Sometimes its more about how you get there then where you end up.

Re: Evinrude 3012 3hp lightwin

Out of curiosity, have you tried a de-carb yet?
In allot of cases these older motors get their rings hung up with carbon. A de-carb service may bust the carbon free, and allow the rings to do their job again.

Might be worth a shot before you pull her apart.

Re: Evinrude 3012 3hp lightwin

RogersJetboat454 said:

Out of curiosity, have you tried a de-carb yet?
In allot of cases these older motors get their rings hung up with carbon. A de-carb service may bust the carbon free, and allow the rings to do their job again.

Might be worth a shot before you pull her apart.

Click to expand...

All ready apart. One piston and bore has gauges, other one fairly clean. Motor ran great on a fishing trip in Canada, and then one afternoon just wouldn't run any more. Luckily had a spare engine. Anyways, it needs to be bored, and replacement O.S. pistons and rings installed to work. Anything crazy I need to look out for when putting all back together? Took pictures of dismantle, and have everything in groups according to assembly. Any advice not matter how minor would be appreciated, I am new to this type of project.

Re: Evinrude 3012 3hp lightwin

Did you pay attention to how the rods, the rod caps, and the pistons were orientated? Even the wrist pins might need to come out a certain side of the piston. I just rebuilt my 1974 4 hp, very much like your 3 hp, and I would have messed it up if I had not had a manual.

DLH