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Over flowing carbs

Cpelcher

New member
Hi. 74' 85hp Johnson. Rebuilt to carbs and clearly screwed something up. Carbs are over flowing with fuel. Eventually stalling the engine. Thoughts? What do I need to do? Thanks!

chris
 
(Carburetor Float Setting)
(J. Reeves)

With the carburetor body held upside down, the float being viewed from the side, adjust the float so that the free end of the float (the end opposite the hinge pin) is ever so slightly higher (just ever so slightly off level) than the other end. And when viewed from the end, make sure it is not cocked.
 
Hi all. Took the carbs off again checked the floats and everything else, they seemed to be in order. Put them back on started her up and fuel was pouring from what I believe are the venturies (spelling). The rebuild kit was pretty straight forward, took a piece off, put the new one on etc. Floats are not upside down, they seem to be parallel as manual suggests. Any other thoughts?

Thanks in advance
 
Floats are upside down. Bet you!

With carb off, bowl off, hold carb in normal operating position, level and flat, float hanging.
Blow into the fuel inlet with your mouth. Air should flow.

Turn carb over, float is now pressing on needle as if to seal off incoming fuel.
Blow into fuel inlet....no air should flow.

If it does...find out why. Most likely float is upside down.
 
The carburetor throat is the venturi. The vertical tube inside the throat is the high speed nozzle.

The carburetors (all) would flood only if the floats were not causing the float needle valve to close... OR... for some reason "all" of the float chamber air vents were plugged. Every time you look into the carburetors, you're simply doing the same thing and expecting different results... Einstein had something to say about that. :)
 
Joe, I think I have the floats too low in the rebuild position, so when in the operating position they would allow too much fuel in the bowl, causing a flooding situation. Does this theory make sense? Is it better they sit higher than lower, but parallel to the carb body?

Will take them off tonight and redo....
 
Joe, I think I have the floats too low in the rebuild position, so when in the operating position they would allow too much fuel in the bowl, causing a flooding situation. Does this theory make sense? Is it better they sit higher than lower, but parallel to the carb body? Will take them off tonight and redo....

See reply post #6.
 
Thanks.
Joe, just for my education, the float being off so slightly can have that kind of effect, flooding the bowl? New to all of this so I'm just trying to understand tolerances etc.
 
Hi folks. Just an update, adjusted floats and all is well. Had them too low, hence the flooding situation when installed. Appreciate all of the help and advice. This forum is invaluable!
Thanks
chris
 
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