RPM's drop to 500 when 3500 is reached

[kimikeking]

I have a 2001 150 Yamaha V-max 2 stroke that suddenly started losing rpm's when 3500-3800 rpm's are reached. Between idle and 3500 rpm's, the motor runs fine, but beyond 3500 is a problem. When the rpm's drop between 300-500 the motor still pushes the boat, but trying to throttle up kills the motor. I had a carb job done in October last year, fuel filter changed 2 weeks ago, gas drained and replaced, have always run Yamalube in the fuel, I just can't figure it out.

 

[99yam40]

Re: RPM's drop to 500 when 3500 is reached

Check the fuel supply system, if no problems there then back to re-clean carbs

http://forums.iboats.com/showthread.php?t=283363

 

[BOAT DOCTOR]

Re: RPM's drop to 500 when 3500 is reached

did boat sit up longer than 3 month if so carbs