Hello everyone. This weekend I was out on the CT river and the boat was running strong all afternoon. While running down the river around 3,750 RPM the motor backfired and I powered down (454 carb) The boat would idle perfectly. I would try and get going again and fuel pressure would drop slowly as the RPM would rise and then go to almost nothing around 3,750 RPM again. We limped back to the trailer at around 2,000 RPM. The fuel pump was not leaking and no fuel coming from vent port (no rip in diaphram). The check valve on the tank has also been removed and all lines are new. This would not be the carb as fuel pressure before the carb is dropping right?


Anyone have ideas on what this could be? Could a fuel water seperator cause this? Is the fuel pump bad even though no leaking?

Thanks for the help.

replace your fuel/water seperator or maybe junk at the pick up in the tank

Check to make sure that none of your hoses are cut on the inside where they slip on to fittings. That can create a flap.

Thanks guys.

Let the testing begin.....