2007 optimax 90 2 stroke bogs down

[WWillis]

I am taking the motor to the shop this afternoon, but wanted opinions, and will post results to help people in the future.

The motor is mounted on a 17'9" spectrum, aluminum hull. Has a 13.25 x 17, 4-blade SS prop.

Problem : after 10 seconds of throttle, on plane instantly, the boats bogs down as if running out of fuel. Sometimes resetting the throttle to neutral then back will give you throttle back for a second or longer. Sometimes it sounds like the motor grunts, like it wants to go but is being held back. I've tried multiple throttle positions, to see if it would run, but soon as it planes out and rpms go up, without adjusting the throttle, it will bog down at 3200-3400 every time. I can hold the boat at 3000 rpms and it runs fine, but I'm ruining everyone else's day with a 3 foot wake.

I have tried a separate gas tank, replaced fuel line to the motor, inline fuel filter, priming ball. No changes.

I will post again the mechanics findings. Thanks in advance for comments and suggestions

 

[SkiDad]

i would suspect the fuel pump.

 

[WWillis]

Just got the boat back from the mechanics... While at the shop, I wanted a new throttle control box installed.
Good news, the problem is solved..... Apparently, even though I see water coming out of the pee hole, it doesn't mean that my engine is being cooled off. He said something about a pop off valve, something that is suppose to move freely, was jammed shut with sand.. It wasnt allowing the motor to be cooled. I know the first thing you're thinking, why didn't I hear an alarm?... Well apparently it wasn't working, it was in the old throttle control box, after the new one installed, it's working properly.... So the boat ran fine at 3200 rpms, because it was in limp mode.
Any thoughts from anyone is appreciated. If admin wants to move this to a solved problem area, feel free.... Thanks again, I hope I've helped someone else