Need help trouble shooting a 1999 Johnson outboard.

putzee52

Seaman Apprentice
Joined
May 25, 2008
Messages
31
I bought a used 1999 sylvan boat with a johnson 9.9 on it. Supposedly it has a 15 horsepower carb on it.

Last year first two times it ran great then began to stall at idle. So i replaced the fuel lines, plugs and cleaned the filter. I also dismantled the carb and rebuilt it. Now having it out today, Starting at high rpm it ran fine. As soon as i dropped it to idle it stalled. Once in gear and running high runs fine, but down in the low rpm it would "Hiccup" and stall.

One other thing i noticed is a white substance, looking like calcium coming from the prop. I saw it on there after removing the boat from the lake and it felt oily. I would really like to make this motor a little more reliable, so any help is always appreciated.
Jay
 

putzee52

Seaman Apprentice
Joined
May 25, 2008
Messages
31
Re: Need help trouble shooting a 1999 Johnson outboard.

One fun piece i forgot to add is it runs fine in my driveway. However as soon as it hits the lake it is time for issues.
 

putzee52

Seaman Apprentice
Joined
May 25, 2008
Messages
31
Re: Need help trouble shooting a 1999 Johnson outboard.

Carb rebuild kit was used. All parts were soaked in carb cleaning solution overnite. Last year. When it would act up if i move the idle air/fuel idle screw you are talking about it would quickly start purring like a kitten
 
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