98 xp ltd won't go over 10 mph

[ckgixxer]

Bought a 98 limited Sea-Doo XP said that he sucked up a rock and would only do 20 miles an hour. Impeller was damaged I replaced it with solas. Put her in the water and 10 to 15 miles an hour Seems like the tachometer is off, in water or out the second you hit it, it hit limiter 7000 rpms. Starts right up, idles good! If I hold it below the 7000 mph it runs good wants to go but runs out of rpms. New wear ring, good solas impeller, pump bearing good. Watch a couple of video of ones running and there is no way it is really at 7000rpms, it shows 7000 on gauge. Is it possible for mpem miss read tach causing it to hit limiter. Any help would be appreciated. All ready did lines and carbs rebuilt. Pop off was low 20's.

 

[Coastiejoe]

If you are certain the wear ring and impeller are good, then most likely the Carbon Seal is bad. Make sure the motor mounts are good. Can you grab and wiggle the engine by chance?

 

[ckgixxer]

No wiggle I even took the drive shaft out it was straight cush drive where all good. Impeller shaft is straight under seat bearings where nice and clean as well. How would the carbon seal effect it? Pump sounds great out if the water very quiet. Solas is very tight to wear ring. 1/4 throttle and the ski is popping from limiter instantly.

 

[Coastiejoe]

If the boot or the CS are bad, it allows air to get sucked out of the hull and then right into the impeller creating cavitation. In most cases, if you leave it on the trailer and back it down the ramp, you can see water enter at the CS at idle and or revved up. If so, it needs serviced.

 

[ckgixxer]

I didn't see a ton of water in the rear of the ski, weather the bilge got rid of it. It was pretty dry.

 

[ckgixxer]

My 98 ltd has the bearing only and I did grease both fitting when I put it back together. So I don't think it has a carbon seal. But I will check it next time I have it down at the water. I did just buy a used mpem last night to give that a try. Thank you so much for your help!

 

[mikidymac]

The 98' did not use the carbon seal, it uses the old carrier bearing/seal setup. If you are at 7,000 at 1/4 throttle and not moving you have something seriously wrong. Ar you sure you are turning that many rpm? The only other thing I could think of is if the splines on the rear driveshaft into the impeller or coupler are stripped.

 

[ckgixxer]

I am only going on seadoo tach and limiter coming on. But even out of the water it just a burp of the throttle and it is bouncing off limiter. I will try to get a video later when I get home. It don't feel like it is hitting 7000 just the computer thinks it is. Just wondering if anyone has seen it.

 

[mikidymac]

My guess is you have something else going on as it would not actually be bouncing off the rev limiter even out of the water unless you were holding the throttle wide open.

 

[Coastiejoe]

Sorry about the bad info on the CS, forgot the 98 used the carrier bearing style.

If you have high revs and poor performance, it can really only be a few things. Impeller, wear ring, or a spline issue. All of these are common. If you are certain that the wear ring and impeller are good, time to pull the shaft.

 

[ckgixxer]

Just tapping the throttle, I find a mpem and will be end of the week. It is the only thing that controls it. My 787 you could burp the gas multiple times where is one the second u gas it's hitting limiter. Can you rev yours without hitting limiter out of the water?

 

[ckgixxer]

Shaft looked good when I had it out, impeller act the same with two different impeller. And no coastiejoe thank you for the valuable input!!

 

[mikidymac]

I can rev my 2001 951 XP out of the water no problem. I do it all the time to blow the water out after riding it just like every other ski I have. Never once bounced it off the rev limiter.

 

[ckgixxer]

Cool! hopefully mpem if not check pick up stator and crank key. I think the mpem is miss counting pulses from pickup. Making it believe it's at 7000 even tho it may be 3000. The only thing that fools me about it is the idle seems right. Keep fingers crossed that this mpem will take care of it. Thank you mikidymac for your help.

 

[ckgixxer]

Update

Got new mpem today fired it up and same thing popping and misfiring all over. So ordered a used stator and pickup and noticed the case is different. The case is a 99-00 and a 4 protrusion mag cup! Can I only change the mag cup and not the fly wheel (I don't have a puller) or go rent a puller and buy a flyWheel mag set up off a 787 Or 951 (98)? Or does anyone know the location of hole alignment for a 99 motor to 98 single coil ski? Also how much damage was cause by my 20Min I ran plus who knows how long he tried figure it out. Pipe was a little gum but normal. Compressions good. Thanks for all the help!!!

 

[ckgixxer]

Well end up being a 99 motor in single coil 98 but! Thanks everybody all fixed 99 motor, pick-up and fly wheel with 98 ski and 98 mag cup worked perfect! Rode it today, what a fun machine. I am pretty sure the protrusion lines up 2 1/2 teeth counter clockwise of the woodruff key. Thanks again! Until the next problem

 

[dieselndoo]

Awesome work, gixxer! Saving this thread for future "know how to"... Thank you