Motor won't spit at high speed

[setterguy]

I'm actually on the water as we speak. 04 yamaha 150 4st. Low speed it's fine. Over5 mph I get no water flow. Any ideas?

[herefish101]

your thermostat is not opening, my guess is there is a total lack of power also. if this is the case there is a way to remove the thermostat and still run the motor, but dont run it for long because over cooling be it not as bad as over heating is still hard on the engine.

[boatfixer]

Setter, more than likely the insert in the impeller is slipping, It needs a new one (impeller). I see several of those every year.

[shortfatguy]

10-4 on the impeller

[setterguy]

Thank you guys. I tried replacing the impeller earlier this year, it has worked fine for 2 months...but this time I brought it in.

[marine_man]

Did that take care of it?

marine_man