9.5 Evinrude 9722

[Jamesd4801]

New to working on these 9.5hps, I got two evinrudes. I just got a 1958 Johnson Seahorse running.

So I also Have a '67 9.5 evinrude. Just was tinkering with it today, I noticed that the top cylinder is hitting the plug, the bottom one is fine. Am I looking at an overhaul on the powerhead or is it maybe something else?

Thanks for the time and advice.

 

[nccatfisher]

What plug are you using?

 

[Jamesd4801]

Champion J4C

 

[Jamesd4801]

This is the top cylinder with the head off.

 

[Jamesd4801]

here is both

 

[Pappy]

James, rotate the assembly and get that piston about half way into the down stroke then stop. "Lock" the flywheel in place with one hand. Take your hand or the wooden end of a hammer or whatever and place it in the center of the piston and push down.If it moves noticeably then yes....you will have to go into the engine. Compare the upper and lower cylinders/pistons.

 

[Jamesd4801]

Found out the plug was sitting to far in the head. Like it was over tightened. I got new plugs, new head gasket, now they dont hit. The pistons and cylinders were solid no noticeable play in them. Why no one ever changes out them thermostats is beyond me. Now replacing coils, points and condensers, Carb kit installed already as well.

 

[Pappy]

Have never seen a J4-C plug come close to a piston top. Specially on only one cylinder. Maybe the plug was dropped or?

 

[Shaugh]

Is it possible that someone put an insert in the plug hole and cut it too deep ?