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]

Re: 1993 Johnson 150

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]

Re: 1993 Johnson 150

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]

Re: 1993 Johnson 150

Check across and then 90* to that.

What is it that you're trying to determine?

 

[James R]

Re: 1993 Johnson 150

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]

Re: 1993 Johnson 150

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

 

[James R]

Re: 1993 Johnson 150

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]

Re: 1993 Johnson 150

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.