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1982 90HP Mercury inline 6 carb problems

pfpienaar0@gmail.com

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I have this 90Hp Mercury inline 6 that leaks fuel from the 2 brass jets in the throats of the carbs.If the motor is trimmed in the running position you can prime the carbs and the primer bulb will get hard with no leaks from carbs. The moment you trim the motor up, about 10 degrees or so, the fuel starts running out the jets. Is this normal for these motors? If not, how can this be remedied? Any help will be appreciated.Thanks in advance. Pieter.
 
Not normal. The float level needs to be dropped about 1/16 inch.

Jeff

PS: I suggest you "vise test" the carbs before going through the hassle of re-installing them. To wit: Clamp each carb in a vise, connect the gas tank to it, and pump HELL out of the bulb. If no leaks, okay; if it leaks, drop the float level a tiny bit more until; it stops.
 
The carbs don't leak fuel when you prime them with motor in running position. When you tilt the carb forward after it has been primed,then fuel will leak from 2 brass jets in throat of carb. All three of them does that.It is as if you put water in a glass and when you tilt it sideways the water will overflow.Hope that made sense. I can pump the hell out of them and there will be no leaks, only leaks when tilted forward.Regards Pieter.
 
That said, ALL Merc carbs leak if the motor is tilted up all the way. I have to do that to store my engine, so I shut the gas off and run her dry first (which I do in any case, with ethanol fuel).

Jeff
 
I found that the pillar inside the bowl,that guides the float, was leaning over to one side. I straightened it out (bending it back )and it cured the problem.

Pieter
 
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