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Leakign Carbs

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ericulvila

Member
After using my 1981 Johnson 75 hp trim my motor all the way up. When I come back to use the boat again there is fuel all over the front of the motor under the air box

Carb lines were checked for leaks already. What else could cause this? Anybody else seen this?
 
i regularly have the same problem. I attribute it to the fuel in the bowl draining out the bleed hole in the top of the carb when at an extreme angle. Its never bothered me, but always requires a little extra "warm up lever" to clear out the fuel that manages to make it to the motor.

Not sure if this is NORAML operation, but based on what I've seen when taking the carbs apart, they are meant to drain this way.

Thoughts from other users?
 
Visualize the position of the floats within the carburetor when the engine is moved from the normal run position (vertical/level) to that high angled, full tilt position. All of the float needle valves are open and should one be using portable tanks that are known to build up pressure due to heat... that pressure will force fuel to be constantly fed to the carburetors which in turn will be dumped out into the face plate assembly. If the face plate gasket is faulty or the hose that leads from the port corner of it to the bottom main bearing area is off or faulty.... you have a hellava mess in the forward portion of the hood pan within a very short time.

Even with a vented built in tank (no pressure fed to the engine), and the carburetors being full due to a normal shut down... that's quite a bit of gas/oil being dumped, and if the gasket/hose scenario as above exists... yeah, it does make a mess!
 
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