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Fuel Pumping Out of Hole on Bottom Carb 45 HP Merc

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acleme1

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"I have a 1987 Mercury Classic

"I have a 1987 Mercury Classic Fifty 45 HP. Been having problems getting on plane, and won't throttle past 3000 RPM when in gear.

Started happening after I had the carbs rebuilt. I had a stuck float, so there was gas pumping through the carb every time I turned the motor.

I took the boat out today, and tried again. I fixed an electrical problem (bare wire on black/white from trigger). Thought that may have fixed it. Still have the problem.

Started it up, and took the cover off to see what was going on while running. I now have fuel pumping out of a hole on in the bottom carb. the hole is on the upper right side of the carb, just above and to the right of the shutter plate.

When started, the carb is sucking the gas through the shutter plate. When I pump the bulb, it won't get completely hard, and gas pumps out of the same hole.

It looks like the top carb has a slotted screw in the same place, but it's hard to see. It looks like the bottom carb has an extra hole...the one that all the gas is coming from.

I believe this to be the cause of my bogging/RPM problem. When I pulled the plugs, the #4 cylinder is washed clean. This would confirm WAY too much fuel is getting to that cylinder.

Not sure what to do next, or what this hole in my carb does? Any help/guidance would be greatly appreciated. AC."
 
"Aaron, the carbs may have bee

"Aaron, the carbs may have been serviced or rebuilt, but the issue still is a carb problem - they shouldn't flood.

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"thanks graham. i took the car

"thanks graham. i took the carbs apart over the weekend, and inspected them for problems. they were very clean (just had a rebuild), so i bent the float tab very slightly on the one that was leaking the fuel. seemed to seat the needle a little better when full. i put everything back together and it seems like i may have fixed the problem. i haven't had a chance to take the boat out to the lake again to test it out, but it looks promising. when i pump the bulb, it gets hard after a few pumps...and no fuel is coming out of the front of the carb.

i'm so glad i decided to take the carbs apart myself. i learned a lot about how the fuel system works, and i can now do a rebuild for around $20...whereas it just cost me $230 to have them rebuilt.

thanks again for the help. ac."
 
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