Help Please! 1997 seadoo challenger 1800 rpm problem and question

[Blue in Yarmouth]

Hi Guys,

I bought a boat in the spring and still haven't got it on the water yet. I have had problem after problem and thought with the recent rebuild of the engine I would be good to go. We got it in the water and we got both engines started which is the most progress I've seen since we bought it, but one of them ( the one that I just had rebuilt) wouldn't rev past 3500-4000 rpms. The other one was fine and ran well, but this one would barely idle and once you gave it gas it would sometimes get a little over 4000 rpms and then die.

I took it to the shop and they say they think it is the rev limiter, and in order to change that you need to change the whole mpem. First, I am not even convinced it is the rev limiter and second, I wouldn't think you need to change the entire mpem to change out the rev limiter.

My questions are this: Does anyone have any idea what could be causing the problem? Does the rev limiter seem like a likely explanation? If the rev is the culprit, do you need to change the mpem or can you just change the rev limiter?

I figured I would check with the experts before I did anything. Please help, I need to know this boat wasn't a complete waste of money. Thanks!

 

[jhjesse]

When the shifter is in neutral the engines will not rev past 3500rpms. I would check the shifter and make sure all the wires are connected and all the fuses (not which one) are good. It is possible that the shifter is out of adjustment or a wire has come loose.

 

[Dr Honda]

The rev-limiter is part of the MPEM... but if it was bad... it would be doing it on both engines.

Check over the ignition, and cut the spark wires back. Sometimes they decay, and you lose spark energy.