Yamaha 50 4 stroke trouble

My buddy just bought new smokercraft with a 50 Yamaha on it. Broke it in according to owners manual & all but keeps fouling up one plug & sputtering anyone know why or how to fix? While fishing last weekend he was just sick & not happy dealership is about 2 hrs away. Any advice would be greatly appreciated!

Bad gas? Or water in the gas?

There has been alot more than normal water in the gas problems this year. Hopefully thats the problem and not something else. Did he ever change that one plug just in case its going bad for some reason?

Thanks, Bill

Run that boat hard after break-in sometimes it takes a little longer to seat rings. WOT for some long periods ang change that plug could be bad

what year is it? the older ones have 4 carbs and it could be a stuck float on one of them. I have a 2000 and it did that this spring. if its newer than it is fuel inject and other problems did arise.

sorry,did not read that he just bought it ,have a dealer check it out,its under warrenty.

Is there a fuel seperator installed? If you are dealing with water in the gas it will help. If there is one installed unscrew it, dump the water, and put it back.

And if it doesn’t have a fuel filter seperator, buy one, they are only like $25 at the most. It’ll only take you a half hour or so to install. Not sure that will help you, but it won’t hurt you.

Hey thanks alot guys gonna give him that info really appreciate the responses!

Try a bottle of Seafoam in the gas.