3hp won't run very long? Why not

[rednebraskao]

I just bought a 1991 3hp yamaha motor with a jon boat. The motor will start on the first pull but will not run very long. I can not keep it running very long at all. Any suggestions on what my problem might be? Any help would be appreciated.

 

[rodbolt]

Re: 3hp won't run very long? Why not

could be a tank vent, tank strainer or a clogged fuel line or sticking needle. can ya give more clues ?

 

[rednebraskao]

Re: 3hp won't run very long? Why not

There is not a lot more details I can give because I have only been able to run it twice. The first time I took it on the lake in ran for about 30 seconds and I fooled around with it got it started again and it ran for about 5 minutes and I couldn't get it started for about 10 minutes, Once I got it started it only ran for about a minute and died again. I ran it in my back yard in a bucket and it did the same thing. I don't know if I am just not choking it right and starting it right or if there is something wrong with the motor itself. The motor is really clean and when it runs it sounds good. That is about all the info about the motor I have. Thanks for asking and trying to help.

 

[rodbolt]

Re: 3hp won't run very long? Why not

ok<br /> now test the compression. <br /> no published specs but it should be 90 psi or above. test the spark. it must be capeable of a 1/2 in gap. if the first two test ok dissasemble the fuel system. did this motor sit long before ya bought it? in 5 min it can overheat if not pumping water.