My 20 hp honda motor (mud buddy longtail) seems to be starved for fuel at full throttle after a few minutes. The tach drops from 3400 or so down to 2000s then would conk out if I continue to hold throttle. I can get it to run fine again if I squeeze the bulb pump a few times. Runs fine at idle. New 5/16 fuel line, new fuel separator, new gas, and new bulb primer. New vacuum pump in motor. If this helps at all, the bulb does not seem to want to prime the line before I start the motor.

Configuration is: tank --> fuel separator--> bulb primer --> inline filter --> to motor


I thought it may be the fuel separator or some loss in suction somewhere.


Any thoughts. Thanks.

You got any quick disconnects on that set up? Are all of the connections tight?

Have you tried unscrewing the cap to vent the tank? I personally would get rid of the separator and get the bulb right by the tank.

Most setups have 1/4" i.d. fuel line. Sounds like you're not getting the right fuel flow rate, as Bigbend suggested the separator might be causing this. You might experiment using straight line from the tank without a bulb first. A friend had a 24 HP Honda that had the fuel pump flow rate problem and had to get an after-market electric fuel pump to correct this.

Here's what I went thru with my 20hp Honda. Loved that motor just always had a fuel delivery issue.

viewtopic.php?t=49356

I would replace the 5/16 fuel line with 1/4 fuel line. if that doesnt fix the issue replace the fuel pump. My old LT would give me the same issues and it was usually an easy fix with replacing the fuel pump.