1993 Johnson 150

[James R]

Model J150GLETG S/N G03249977.
Pulled the heads. Trying to measure the good cylinders but dont have the manual for this one. Wiseco calls for 3.601 for standard however my measuring, having zeroed, my bore gage indicates .007 undersize on the three good ones. Maybe this is a James Bond special.
Need help please

[Dhadley]

Where are you measuring? Are you using a dial bore gauge or a snap gauge?

Yes, 3.601" is what they are from the factory.

[James R]

First, thanks for the rapid response.
About one inch in and using a dial bore gage set and rechecked using electronic vernier. Dont have a master for this size. The vernier checks out ok. Would expect some variance on precision perhaps .001. Use this technique frequently with success.
Jim.

[Dhadley]

Check across and then 90* to that.

What is it that you're trying to determine?

[James R]

Trying to determine if a hone will do the job or if these three need a bore.
Roundness is good but still cannot measure actual size. I'll play a little more. Something is not right.
Thanks for the response guys.
Jim.

[Benny1963]

if its tore down take it to outboard machine shop and the will usually mic it up and check holes for roundness

[James R]

Thanks for the responses. I now have a manual and the bores called up are 3.5995-3.6005. The bores still show some cross hatching so there is little wear. Waiting on a 3-4 Micrometer so as to master my bore gauge a little better. Will keep you informed and thanks again.

[Dhadley]

OMC changed the spec to a min of 3.601". You want to use that for standard and add the os to that. Not 3.600. Trust me.