just recently i started having problems with my engine on my bass boat. it ran fine all day and then towards the end of the day it got to where it wouldnt wont to plane out. didnt think much of it until the next day when it would plane out at all. changed the spark plugs, but no luck. switched the ignition coils and still nothing. a black residue is starting to collect on the piston and spark plug in cylinder 4. i assumed that it was unburnt fuel but now i am not sure. it could be oil but why would it only be in cylinder #4, which is on the bottom most cylinder. does anyone have any input? the next thing i can think of would be the power pack. the engine will idle fine but as soon as you put it under load it boggs down. you can feel it missfiring/bunking/surging. I have a club tournament coming up on the 19th and i have no idea what is wrong.
