Earlier on, I posted that only one of my cylnders was working but now after a few hours of trial and error, it's fixed. If anybody guessed spark plugs, you're right! Any suggestions on which spark plugs work best? Also when i got everything in working order after going at those plugs with a wire brush, i was cranking on my gas and some heavy black smoke shot out of side that was working the whole time. SHould I be worried?