I have a 2011 60 hp Yamaha fuel injected 4 stroke on my pontoon boat. The problem started at the begin of the season. I took off from the launch and the boat ran for about 5 minutes then died! I tried to restart the boat and it started and idled fine. When I put it into gear and tried to accelerate it would die again. So I tried one more time and the same thing happened. I then pumped the ball and the boat started and took off again for about 5 minutes then the same story... So I immediately thought fuel pump or the ball was bad, I also looked over all the fuel lines for cracks or holes and found nothing. I also checked the tank for water and the fuel separator and found no water. I had my girlfriend drive and I stayed in the back and pumped the ball and the boat ran fine until I stopped pumping. My next step was to replace the primmer ball and the fuel pump that is manually operated by the motors compression. I started with this pump because it was cheaper to replace than the electronic one. So here is the confusing part. I replaced the pump and ball and took the boat for a ride. I eased into the throttle and ran the motor around 3000-3500 RPM and it ran perfectly for like 15- 20 min. I then pushed the throttle to full and the boat ran for 2 minutes and bogged down to 2000 RPM. The motor would then begin to pulse between 2000 and 3000 RPM. When I moved the throttle back to idle the motor would run smooth as can be and shift into forward and reverse with no problem. It would then allow me to accelerate to about 2500 RPM then begin to do the pulsating thing again. I then return the motor to idle squeezed the ball one time and the motor will run fine like before until I try to go above 3500 RPM, then is the same story as before. So in replacing the one fuel pump it made the situation a little better but didn't fix it. So should my next action be the electronic fuel pump? or is there something else i'm missing. Please help.
I tried running the boat with a different external tank to and no luck.
I tried running the boat with a different external tank to and no luck.