Just took my boat out for the first time since December, and I'm only
getting about 80% out of the motor. Its a '95 Johnson and I can't even
get it to plane out right now. Tried replacing the sparkplugs but no
luck. There's a lot of old gas in the tank right now, could that be
part of the problem? The engine isn't sputtering or failing to start.
It's as though I just can't get that extra Ummph to plane out.

Suggestions?