mixture screw, bump yamaha

[bumpy]

I can have a fine idle and then some trips when im in the water the motor stalls on me, so is this a mixture issue or gas issue . im thinking the vibration from the water and motor is making my screw move a little, any symptoms on what might be the issue yamaha 8hp 2 stroke 2003

 

[bumpy]

Re: mixture screw, bump yamaha

any help

 

[Yamajoe]

Re: mixture screw, bump yamaha

Bumpy, could be fuel, spark or compression. have you tested for these? More likely it's fuel related but the sudden stall points to electical; check you kill switch wire (i think it is white) from the red stop button to CDI to ensure wire has not shorted.

 

[deejaycee_2000]

Re: mixture screw, bump yamaha

The right setting for your air/fuel mix screw is 1 & 1/2 turns outwards from soft stop ..... also make sure that you have enough ventilation at the tank .... if all else fails, check your reed valves ....