i have an OMC 350 that has a weird intermitent stumble, only when trying to accelerate once it works past a certain point it is fine. working the throttle back and forth seems to hit a sweet spot and it goes great. until you bring it back down and try to bring it back up....... fuel filter...
i have a 1986 mark twain 210 with a 350 omc engine and a omc 800 outdrive. and boy do i need help big time....... i have tried everything i know and then some... my boat overheats only on plain. it will sit at 160 all day long. as soon as i gas it up and get it up on plain the temp starts...
