2004 Yamaha 225hp four stroke

grady19 · 11-03-2009, 04:15 PM

Dear A1,

I have a 2004 yamaha four stroke 225hp. Over the summer the engine blew up so I sent it off to you guys. You'll rebuilt the engine and ship it back to me in no time. I was very impressed with your service. I have ran the engine for a month now and not had any problems with it but one thing. The engine runs great at idle, cruse and top end. The problem is my top end is only reving at 5300RPM where before it reved at 6000 RPM lowering my topend speed. I am running the exact same prop as I did before being rebuilt and running in the same conditions. Is this a tunning problem that can be fixed easy or a rev limiter problem?
Thank you for your time,
Bradley Gray

davidkuhlmann · 11-04-2009, 08:15 AM

Bradley sounds to me like maybe you have the outboard down lower on the transom which will lower your RPM's by dragging the LU. The motor needs to be adjusted to have the cavitation plate even with the bottom of the hull or just above. To check the engine height take a friend for a boat ride and get to WOT and full trim if you can't see the caviation palate then you need to raise the motor by the number of holes to inches neede to get the correct engine height. The caviatation plate needs to be just dry some splash is ok but not below the water when at WOT and Full Trim.

Hope this helps.