Maybe you know the answer !

[nusslejj]

We recently purchased a very nice 2011 Seadoo Speedster 150 with a 215hp Supercharged engine and 127 hours. One owner, winterized professionally, stored indoors. Starts easily, accelerates well, but it doesn't hold RPM's very well. Because I am not familiar with the engine, I don't know if this is how the engine behaves, or if I should have it looked at. Yesterday we were tooling around the lake at about 2100rpm and it tends to wander up/down 80-100rpm. Is this the behavior of the engine - i.e., it won't hold rpm's perfectly like a car engine ? If not, what might be the problem ?

We live in NE Ohio, and there are precious few places I can take it to be serviced.

Thanks for the help !

 

[10forty2]

My 2005 Speedster 200 with twin 155 SC Rotax engines holds RPMs just fine, so I would say no, that's not normal. Just thinking out loud with you, I would first think of simple things like a loose throttle, but that would tend to only manifest as losing RPMS and not increasing rpms as the throttle slid back towards idle....mine did that when I first got it, on the port engine...I had to increase friction on the throttle handle to solve that one. My next thought is possibly old/bad fuel, but that would tend to also manifest in cranking, accelleration and pretty much everything else associated with the engine running....it would likely run rough. Next thought, might be the wear ring or the impeller causing it to cavitate slightly.

 

[RANDYD]

I just sold a 08 Speedster 150 215HP with 52hrs it did the exact same thing I never worried about it.

 

[C9R0J0]

My 2006 215hp also does this sometimes. It's annoying to say the least, but nobody on this forum seems to have a definitive fix. I suspect mine has the original fuel filter in it so perhaps that could cause the problem. I intend to change that for next season.

 

[NHDave]

I have the same issue with mine. I've looked at several possibilities without finding anything. I am now looking at gasoline octane. Premium fuel in my area can be 93 octane or 89 octane, so I have started being careful to only run 93 octane and the problem seems to have gone away after a couple tanks of the 93 gas. I've only been doing this for a few weeks so maybe it's just my imagination but time will tell.

 

[gacekj]

I also only run 93 Octane in my Speedster 200, as I was told by the dealer when I bought my pontoon with a Yamaha outboard to always run gas with least amount of ethanol if I could not find marine gas - he named BP Amoco's Premium grade, so that's what I use in both boats. I get great performance and have not noticed any drop off in my RPMs though I have not actually paid attention to it. I will watch next time I'm driving and will update again!