Thread subject: Whaler Central - Boston Whaler Boat Information and Photos :: Motor Issues 40 Johnson

Posted by dirk109 on 07/29/10 - 8:48 AM
#1

So, I have this new to me 1961 Johnson 40. The motor has never really run right. 2 weeks ago, It went down to 1 cylinder while I was using it. I brought it back to my mechanic who claims that some times the point closed up. He fixed it and sent me on my way. I used the boat yesterday and the same thing happened. It had more power then the last time, But still was doggy and ran rough at lower speeds. I pulled both plugs and one was more black then the other. Is it the points again? My mechanic is over an hour away and I don't really want to keep on bringing it back if is something I can do myself. Any help would be great.
Thanks.....

Posted by rvschulz on 07/29/10 - 2:02 PM
#2

when i had an 18 evinrude - i went on eBay and bought a "tune-up" kit for about $15 - ithink it included spark plugs. that much is a do-it yourself motor. drank a bit of fuel considering and was loud, but ran well after a tune-up.

Posted by rody on 08/02/10 - 7:57 AM
#3

I've had the same with my '75 johnson 40.
I thought it was the ignition too. But it turned out te be a dirty carb. Even after cleaning it myself with carb cleaner it didn't work.
Carbs, especially when they're that old, tend to gather a lot of debris that cooks up in the internals. Best way to solve this is putting the carb in a ultrasonic bath. It did help for me. Mine is runnung like new, apart from the rubber mountings which ran dry...