force carb leak

[wpack5]

Have a '92 force 120. Whenever the throttle is advanced to 3/4 or WOT, the carbs will occasionally spit some fuel from a hole at the top (? overflow valve). I don't seem to be getting much more power from the motor at this point. I have replaced the needles and seats thinking that this might be the problem, but doesn't seem to have helped. Have drained the fuel and decarbonized as well. Any comments are appreciated.

 

[bKelly]

Re: force carb leak

The float might be sticking causing the fuel to contune to pump into the carb and fill up the boal and squirt out the excess fuel out of the carb.

 

[Yepblaze]

Re: force carb leak

Why do you have your head in there at 3/4 throttle anyway? Does it leak a lot of gas or is this just some residual spotted?<br /><br />Probably a bowl vent. At those rpm's it might just have to fuel in the bowl that excited it's getting shook out the vent?<br /><br />Perhaps it is making some air in the fuel supply (whith a small airleak somewhere before the fuel pump)and has to exhaust all the air from the bowl taking some fuel with it.?<br /><br />Maybe it's a design thing....................

 

[PaulHolcomb]

Re: force carb leak

You should probably be checking your fuel pressure to make sure the pump isn't surging. To much will cause the floats to bend and cause too much fuel in the boals. When at 3/4 to WOT the needles are lifted off the seats as far as they will go. If the fuel pressure is too low then this will cause the fuel to start atomizing within the float bowls and could blow out of the vents. This could also be why you find no more hp between 3/4 and WOT, NOT ENOUGH FUEL!!! And what about timing and advance? Think about it.