johnson outboards

[johnny mav.]

I have 2 1989 200h.p. johnson outboards that start fine and run fine up to 3000 rpm then they start to misfire.
any ideas?

 

[boobie]

Re: johnson outboards

Any warning horns ??

 

[johnny mav.]

Re: johnson outboards

hot horn but neither motor was anywhere near hot.

 

[boobie]

Re: johnson outboards

Are these motors on the same boat ??

 

[multimech]

Re: johnson outboards

Yeah, the thing they have in common is the fuel supply (Restriction, crap fuel, etc). Batteries don't matter because they will run all day without a battery once started. They both won't have the same problem at the same speed, unless you got really really unlucky. Maybe one is having the problem and is loading the other one more and you are assuming they both break up. Need more info.

 

[johnny mav.]

Re: johnson outboards

yes

 

[johnny mav.]

Re: johnson outboards

when i rev them at idle only the one that read hot misses

 

[multimech]

Re: johnson outboards

Do a spark and compression on both engines. Pay attention specifically to the one that has the rev problem. Missing in idle out of gear would indicate a problem that may be easy to find. Take temp readings all around the heads when you have it in the water. If okay, try it at a higher speed. We need to pinpoint where this problem is to find it and fix it, if possible. We don't have a lot of specifics right now so it is difficult to know where to start.

 

[johnny mav.]

Re: johnson outboards

thanks will do.