A little help please with a 1994 Johnson 15 HP 2 stroke

[Black Bear]

My 2 stroke 1994 Johnson 15 H.P. starts fine and usually runs fine but sometimnes it just sputters like it is only hitting on 1 (or less than cylinder). Sometimes it fixes itself and runs fine only to sputter again. Any ideas on what to do first to correct this proiblem? Obviously,I will replace the plugs.......anything else I should do? Thank you

[fasternu]

I was once told "a motor needs gas, air, and spark". If the gas is good, then either the carbs are dirty, the plug wires are bad, or maybe the coil is bad. I would lean toward the coil. Pull the plugs and check the spark. If it consistant, then look toward the carbs. If the spark is intermittent, then look at the coil.

[thedeadsea]

If you verify spark is good on both cylinders, try running a tank with Seafoam through it. If this doesn't fix the problem, clean the carb.

Steve