I have a Mercury Blueband 20hp with some power issues.<br /><br />The story goes, in the beginning myself and my friend that has some outboard experience found that the engine was running on just one cylinder. Back then both plugs were firing.<br /><br />We thought it was the ignition system so changed most of it. It worked fantastic for about 5/10 mins, giving full power, then it started dying/loss of power. Pumping a little more fuel into the carb didn't help, nor changing all the fuelline system (eliminating air getting in). <br /><br />Having taken out the plugs today, I found them both fouled up with a thick black oily covering, both sparked fine on both leads but the engine has is now again running on just one cylinder. <br /><br />The engine only starts when the one lead is on the one spark plug. If I change leads on the one cylinder that's working, it just misfires/spits.<br /><br />Has anyone any idea as to the problem/solution, as both myself and my friend are stumped.<br /><br />Cheers, Ryan.
