Trouble gaining speed with 40 h.p. johnson

wildman59

Cadet
Joined
Apr 6, 2009
Messages
18
I have a johnson 40 h.p. motor that has always ran great, but recently it has developed some kind of a fuel problem I think. The motor will start just fine, and go into gear but when I try to accelerate, it bogs out and dies. If im in nutreal and rev it up it will hesitate for a second, then it will clear out and rev up but when i'm in gear driving it will die upon accelerating unless I move the accelerator very very slow and slowly creep up to speed. I have fresh gas in it, and new plugs, any idea on what this could be? Thanks for any help.
 

crxess

Chief Petty Officer
Joined
Apr 30, 2009
Messages
559
Re: Trouble gaining speed with 40 h.p. johnson

Sounds like a partial restriction in the High speed passages in the Carb. Need a tear down and clean, possible rebuild.

Quick open throttle rams full air flow but limited fuel starves motor out.

Partial choke should verify
 

fergie

Recruit
Joined
May 29, 2009
Messages
5
Re: Trouble gaining speed with 40 h.p. johnson

check to see if your timimg advance plate is sticking, had same mo with my 85 v4.
 
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