1996 Johnson 9.9 carb problem???

[EVAN]

I have a Johnson 9.9 that has been sitting for over a year. I got it out the other day and mixed up some fresh gas and started it up. It starts and runs good, but when you let it sit and idle, it slowly idles down and dies. If you pull out on the choke just before it dies it will idle back up and run a while before it tries to die again. After it dies, you have to choke it to get it started again.

That being said... I figured my carb was gunked up, so I mixed some sea foam in with my gas and ran quite a bit through my engine. After a while all the problems seemed to go away and the engine was running great, no idle problems and it would start on half a pull after getting warmed up.

Well, the engine sat for a few days, and I went out to start it... and now it's doing the same thing it was before I ran the sea foam through it. I thought I had it fixed, but now I'm not sure what is going on. I figure I need to rebuild my carb, but I don't want to tear into it if that is not my problem. Any advice would be appreciated.

Thanks,
Evan

 

[Bifflefan]

Re: 1996 Johnson 9.9 carb problem???

probably could still use a carb rebuild.
Mine had a simular idle issue, after rebuilding the carbs she runs like a top.

 

[oldrudedude]

Re: 1996 Johnson 9.9 carb problem???

It sounds like a fuel supply problem. There may be some contamination in the fuel tank that is slowly accumulating in the carb float bowls. Regardless the carbs should be cleaned and reset with special attention to the slow speed jets and needles. Make sure there is no restriction or air leak in the fuel line and that the tank vent is not plugged.

 

[EVAN]

Re: 1996 Johnson 9.9 carb problem???

Is rebuilding the carb a pretty easy thing to do? Would I need a manual in order to do it correctly and get all the settings back in the right place? Is there any free literature available on rebuilding these carbs?

 

[OptsyEagle]

Re: 1996 Johnson 9.9 carb problem???

Have you tried adjusting the slow speed jet on your carb. Try turning it counter-clockwise 1/2 a turn and see if that helps. If it starts running smooth then the problem was your motor running too lean. Search for joe reaves carb adjustment on this site and follow the procedure.

If it doesn't work then I am in the camp of carb. cleaning. After that, you will need the carb. adjustment procedure to get it set properly.