Yamaha 150 Cuts off at high and midrange rpms...

[broz]

Yamaha SX150TLRY OX66 The engine is shutting off after about 2 minutes at 3000 plus rpms.It turns off then will start right up again. It did not do this last season . Any ideas?

 

[Five Spice]

Re: Yamaha 150 Cuts off at high and midrange rpms...

I have a 200hp that was doing the same thing, but at a higher rpm. What I found out was that the O2 sensor was fouling up. You can take it off and clean it and see if that takes care of the problem. It's a pretty simple process. There are a couple of threads on here that explain what to do and I think one has a link to show how to clean with flame. A new O2 sensor is around $400.

 

[Home Cookin']

Re: Yamaha 150 Cuts off at high and midrange rpms...

also tighten all ground wires, battery and motor. A slight vibration on a loose connection can cause it to interrupt, although I don't know that they often shut down completely. But with the electronic "impovements" they might.