Scottpeceny
New member
Grabbed a 1979 100 HP Johnson for cheap- I have a 75 HP Evinrude that's also 1979 and figured I could use the Johnson for the trim motor and a few other parts at the very least. Before doing so, wanted to see if I could get it running. Knew it had bad compression in one cylinder when I bought it, and now I'm finding that two of the pistons had blown rings. My question is this- I know for sure I need a new piston for cylinder one (not pictured). Is this piston (pictured) salvageable? Is the cylinder damaged to the point I need boring? The cross-hatch is no longer apparent, at least not without looking very hard.
It's looking like I now need two new pistons and a new gasket set at the very least, with no guarantee of this motor running at all, let alone for another few years.... BUT, nothing else seems like it's in too bad of shape, and it could run for a lot longer if repaired... You just never know.
What do you think? Piston no good? Need re-boring? At what point do I bail on this project, knowing the motor is only worth what? $1,500? And that's if it runs.
It's looking like I now need two new pistons and a new gasket set at the very least, with no guarantee of this motor running at all, let alone for another few years.... BUT, nothing else seems like it's in too bad of shape, and it could run for a lot longer if repaired... You just never know.
What do you think? Piston no good? Need re-boring? At what point do I bail on this project, knowing the motor is only worth what? $1,500? And that's if it runs.
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