8hp Johnson quits when running - unless you pump the choke just right

[Ricardo]

Model J8RESR<br />Serial B08445569<br /><br />Engine starts ok but tends to quit unless you constantly play the choke in and out. I found a broken plastic piece that looks like a roller arm that rides along the spark advance cam and pushes on the throttle plate on the carb. Tried to run the engine using my fingers to manipulate the throttle setting on the carb while advancing the spark via the throttle on the tiller. Same thing..tends to run ok for a short while (10 seconds) then wants to quit if i don't pump the choke in and out to keep it going. I would like help finding that plastic throttle-carb part but fear that even afetr I replace it the engine may tend to quit based on my trouble shooting work-around with the broken piece.

 

[JB]

Re: 8hp Johnson quits when running - unless you pump the choke just right

Hi, Ricardo.<br /><br />I think you have 2 problems.<br /><br />Your engine is not getting enough fuel. Most likely cause is a gummed carburetor. Other possibilities are fuel tank venting and pickup restriction, air leak in fuel hoses, weak fuel pump.<br /><br />The roller missing from the stator plate follower is misadjusting your carb/ignition linkage.<br /><br />For mored detailed advice, go to www.outboardrepairs.com.<br /><br />Good luck.

 

[Ricardo]

Re: 8hp Johnson quits when running - unless you pump the choke just right

Started my trouble shooting with fresh fuel...new fuel tank(vent open) new fuel lines. Gum in carb sounds like a good place to start, can it be cleaned without removal?...where is the fuel pump and how easy/hard is to overhaul....also read on an old post that there is a tiny hose in the fuel cup on the carb that might get old and brittle. Any more experience on that...Last question about the broken part....small plastic carb components...can they still be purchased? Greatly appreciate the help. Thanx

 

[JB]

Re: 8hp Johnson quits when running - unless you pump the choke just right

Howdy, Ricardo.<br /><br />Before you attempt to work on your engine you need a Manual. Aftermarket manuals are available here (bottom of page, click on Repair Manuals.<br /><br />The carb cannot be properly serviced without dismantling it.<br /><br />Carb and fuel pump overhaul are quite easy IF you use a manual.<br /><br />Your engine is a 1990 model. Parts are available at Johnson dealers and at NAPA Auto Parts stores.<br /><br />Good luck.