97 Yamaha 60 runs slow / rough past fast idle.

[davidmf]

Engine ran great last time out about a month ago. Today I filled up the almost empty tank & carefully measured oil mix. In the water she cranked & idled without a problem. Started heading out and pushed the throttle handle down wide open only to reach about 5-8 mph and turned around to see the engine rumbling & vibrating a lot.<br />I have a fairly new fuel filter and a fresh tank of gas. Any suggestions will be GREATLY appreciated.

 

[aeronutt29]

Re: 97 Yamaha 60 runs slow / rough past fast idle.

The two things that jump out at me to check for are a clogged high speed jet in the carburetor or a broken reed valve. More likely the high speed jet. I'm not at all familiar with your specific motor, but they all run on the same principles....