Yamaha Experts-2000 Yamaha 225 OX66 EFI-WOT Dies

[wi1p]

My dealer has been unable to resolve problem/s with intermittant WOT cut out on my 225 Yamaha on my Cobia 244 for three months. Problem only occurs after 20-30 minutes of slow going as thru a "No Wake Zone" then hitting WOT; after 2-3 minutes at WOT engines dies without warning. Restart is fine and it may or may not run at WOT again. Danger is everyone on board is thrown forward when engine dies. All Fuel filters replaced, High Pressure Fuel pump replaced, oxygen sensor replaced.. no changes. I purchased boat three months ago. Original owner reported same problem.<br /><br />Any thoughts or suggestions would be appreciated.<br /> [*]null

 

[skelly]

Re: Yamaha Experts-2000 Yamaha 225 OX66 EFI-WOT Dies

Unhappy Boater !! I feel your pain . I have a friend with the same problem, His motor is a 99 225 Yamaha and dose the same thing . Please post if you find out what the problem is <br /> <br /> Thanks Skelly.

 

[seahorse5]

Re: Yamaha Experts-2000 Yamaha 225 OX66 EFI-WOT Dies

Heat soak or vapor locking can cause similar symptoms. The best bet to find if it is a fuel related problem is to "Tee in" a vacuum guage and a clear piece of fuel line into the fuel inlet fitting (per the service literature). Then hook up the fuel rail pressure gauge. Duplicate the running conditions and watch the line for bubbles, the vacuum gauge for more than 4" Hg restriction, and the pressure gauge for any drop when the engine starts to die.<br /><br />The 2 to 3 minutes of running then quitting could be the vapor separator tank running dry as it holds about 13 oz. of gas. The electric fuel pump also runs at 2 different amperage settings and may have an electrical problem when switching to the high speed mode.