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Carburetor issue

R

Red-Rob

New member
This is my first time posting but a long time follower of this forum so thanks in advance. I have a 2003 johnson 50 hp (J50PLSTD) that is giving me carburetor problems. Originally I wasnt able to reach WOT the engine would die out at 2500 rpms. I cleaned and rebuilt the carbs with new floats, gaskets, needles etc. Now it idles rough and smokes. When I place two fingers across the air intake of the upper carb, the engine dies. When I block the air with my hand on the lower carb it keeps running like nothing has changed. I can feel it pulling a vacuum on my fingers and it blows fuel back at me. I switched the carbs and the problem follows the carb. I've taken the carb apart and everything looks normal. I have a Johnson gauge tool to set the float height and the float is set the same as the other. Any help would be appreciated.
 
Thanks, I pulled everything apart that I safely could. It all looks clean, no varnish anywhere. I'm just wondering if I block the air from the intake then it has to be getting air from somewhere otherwise I would think the engine would die. I may have to start with new gaskets and see from there. I was wondering if there were any place I should concentrate for cracks. I will definetly try what you recommend when I get new gaskets maybe I missed something the first time.
 
Thanks for the help but the problem was the carburetor cover gasket was in backwards. I lined up the bolt holes but didnt notice if you flip the gasket over different air/fuel holes open. There are 2 small black plastic dowels in the cover to tell you which way it goes. Once I put it in right the engine ran like a champ. With the gasket in wrong I was never able to get the mixture right causing the poor idle and smoke.

50/50 chance on the gasket and that is what I got, one right and one wrong.
Thanks again.

Human error is the reason for a lot of grey hair. Every one of my grey hairs I've earned and wear them like a badge of honor.
 
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