A friend's got a 89 sport nautique with a Ford PCM 351 engine with Holly carb.
While trying to accelerate the boat starts slipping and reducing speed, cutting out and acts inconsistent, he's tried different gas stations, using gas cleaner &/or water removal from the gas tank to try and troubleshoot, but nothing's helping. Also he replaced all of the spark plugs still cutting out and some backfiring type noises persist. We think it might be the carb. but not sure... Anyone have similar problems? Any suggestions?