91' Yamaha 40 hp cutting off when running for awhile

[delbass]

Hi There<br />Can anyone help. I am running a 40 hp 1990 yamaha and as i am running down the lake after awhile it will slowly bog down and then cut off. After pumping the fuel line up again it will run for another 200 yards then cut off again. Does anyone have an idea of what is going on? It really doesnt haooen when I am idling, just running on plane. Thanks for any help you can give.<br />Trevor

 

[31900]

Re: 91' Yamaha 40 hp cutting off when running for awhile

Sounds to me like a fuel pump problem. Check your fuel line from the tank to the motor for air leaks. Check the non-return valve and if all ok go to the fuel pump. Even a small hole in the diaphragm will cause the problem. Repace the fuel pump rather than repair it. Is your fuel filter OK?