2002 Merc 240 EFI Top Speed Issues

[mrmetro]

Hi folks,

I have a 2003 Seadoo Utopia 205 with the Merc 240EFI. I'm noticing a top speed of 35 mph WOT. The RPM's are at 6000. New plugs, no cavitation, wear ring perfect, calm lake.

I've noticed when I move the throttle lever forward it moves roughly a quarter of the full travel before I get a response from the engine. I'm assuming this has something to do with the top speed?? I'd like to think if I wasn't up to 6000 rpm at WOT my theory would make more sense.

Any suggestions would be helpful.

 

[GAlivin]

Are you sure nothing is lodged or blocking the pump? Do you have the original surge grate on the pump? If you do, you may have sucked up something that is restricting H2O flow through pump. Inspect for debris.

 

[GAlivin]

I'm also thinking maybe your Reverse gate is not adjusted correctly. This could be creating a resistance to your forward thrust. Also as you pointed out...check your throttle adjustment. Good luck.

 

[biffdotorg]

I've noticed when I move the throttle lever forward it moves roughly a quarter of the full travel before I get a response from the engine.

If this was happening on my boat, the first thing I would start looking at is throttle cable adjustment. If you are moving the throttle and the engine is not responding, then the cable is not adjusted properly.

You should be able to make that engine blip by just banging on the throttle handle from fully closed. When idling around a dock or our lift, I hardly touch the throttle to get the response I need.

90% sure it is out of adjustment. A service manual would tell you where it should be, but throttles are pretty straight forward. With the cover off the back, you should be able to see the cable moving components in the engine compartment while someone moves the throttle in the captains seat.

Good luck and report back. Most of us have the service manual if you need advice on where the adjustment is.

 

[Dr Honda]

I would also look at the throttle cable... but since you are getting to 6000 RPM... that's full power. (more or less) I also would suspect some sort of restriction in the intake.

How are you checking the speed? The factory speedo is not very accurate.