225 Yam OX66 Saltwater Series RPM Spikes

[Arnzo]

Hi all<br /><br />Great forum and first timer here. I have twin 225 OX66 on a Pursuit 2870. I've had the boat for three years and its been pretty solid. I have had one engine issue that I have not been able to solve. If I try running the boat with the engines at 2400 to 2600 RPMs and the bow plowing (i.e not on plane), the engines....usually the port engine.....will spike sometimes as high as 3900 to 4200 RPMs. Boat runs pretty good on plane, sweet spot is at about 3400 to 3600 RPMs but sometimes one of the engines will fall back forcing me to continually adjust the trottles. No issues at no wake speeds. Any thoughts on this. Sound like it might be the trottle contols instead of the engines? Thanks in advance.

 

[rodbolt]

Re: 225 Yam OX66 Saltwater Series RPM Spikes

sounds like excessive load due to barely planing. ya need to keep it up on a solid plane with the proper trim attitude. if the throttle tension is loose the handle can move back. has all the maint been done in accordeance with the service manual at the specified hourly and annual guides?<br /> I have found that if propped corectly. RPM about 5600 at WOT that motor likes to run between 3800 and 4500.post the model numbers and the maint history.