Seadoo 720 Power Loss

[mavarano]

Hello,
I was wondering if i can get someones 2 cents on an issue im having since people on this forum seem to know what there talking about. i have a 98 sportster 1800 with the twin 717 motors. one engine is losing power. the rpms were at 7000 rpm at first and its slowly decreasing, now its at 4500rpm at full throttle and sputtering. the compression in both cylinders is 148-150 psi. the other motor is running great and has the same compression. i am just out of ideas and am considering replacing the engine. please help me out.
Thanks
:rant::rant::rant::rant::rant:

 

[Dr Honda]

if you have 150 compression... then replacing the engine wont do anything.


I'd start with cleaning the carbs, and checking the fuel system.

 

[Bills86e]

I bet you have old gas in it. Lot of that lately.

 

[mavarano]

I have had the boat for almost 2 months now. ive filled it up 3 times so far and the first time was with 100 octane just to clean out the motor a little. i only use 91 octane in the motor except for that one time. The other motor is running great. its at full power. i think i will check the fuel filter. the carb was running good when i first got it. is it possible for it to suddenly get clogged or go bad.

 

[mavarano]

Also it is at full power when its out of the water and has a hose hooked up. the motor revs all the way to 7000 rpm no problem. but when its in the water and has a load it slows down to 4500 rpm and sputters between 3500 and 4500 rpm at full throttle.

 

[Bills86e]

Deffinatly fuel circulatory related.