Carb Adjustments/fuel issue

[ledzeppelin135]

Hello, I recently rebuilt the fuel pumps on my 83 merc 50hp because you could watch the fuel level drop through the fuel filter. I assembled it all and it seemed to be corrected until I was out at the lake and I hit a descent size wave and it lost fuel pressure and I could only go to about 2500 rpm before it would start to bog out. The fuel level in the filter was very low and even if I pumped the bulb it would not help the rpms get back up. I took the carbs off and noticed that the fuel pumps I installed were correct but one screw on each pump was somewhat loose as I could not get to them to torque them down. Also, I noticed on the fuel lines that the ties holding them together were very loose so I got some hose clamps to torque those lines down to get them tighter. I am not sure if this sounds like it could be some sort of an air leak or something.

Also, I am wanting to check the two measurements for the floats to make sure they are set and I am wondering if somebody can explain what I measure and where I measure from. My repair manual is making no sense to me.

Thank you,

-Chris

 

[oldman570]

Re: Carb Adjustments/fuel issue

Most manuals give the distance of the floats from the top of the float to the carb housing with the carb off the motor and the bowl off , and the carb turned upside down. Lose fuel hoses anywhere will let air into the fuel system and cause it to run lean if it will run. Lose screws on the pump will do the same .
Oldman570

 

[Faztbullet]

Re: Carb Adjustments/fuel issue

Just a note ....the filter will never be full when running

 

[ledzeppelin135]

Re: Carb Adjustments/fuel issue

but there should always be more than a 16th of an inch of fuel in it at idle; and when you say the carb housing, it that the outer end of the float or the inner part of it?