Recently had a bog on takeoff. I'd experience a bog or stumble. Maybe 7 or 8 times and then it would clear up. Suspected fuel delivery issue. It had been a while so I reworked the fuel system. Pulled the injectors and sent them off to be cleaned and flow tested. Replaced all the fuel lines from the tank to the engine as well as a new primer bulb. Replaced the internal fuel filter and the racor fuel water separator I have installed (no water found). Pulled the VST and replaced the internal filter. No appreciable dirt found. After all that, the takeoff bog is gone. I have noticed now (possible before but I can't be sure) that as I come off plane to lower rpm I get stumble or bog. It only occurs at specific RPM's (didn't make note of that rpm, sorry). When boat is just in gear no issues and just past that specific RPM range where it occurs, no issues. Wondering if the fuel pressure regulator is the culprit. I believe the fuel pressure regulator helps in transitions keeping the fuel pressure consistent. It's not keeping me off the water and doesn't die. It's now duck season and I'll be switching to my mud boat and won't run it again until Jan or Feb. Any ideas what may cause a low speed stumble at specific RPM's?
