96 787 xp won't rev up

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slangford

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Having an issue with the engine not reving up. Starts and idles fine but when you get on the throttle it seems like its cutting in and out. I ran it with a spark tester installed and it looks like the spark stops and starts but only when you rev it up. All this seemed to take place after sucking in a piece of 1/4 inch nylon rope. Managed to pull it all out. Any way this is connected to my problem? Looked through lots of threads before posting this.
 
What have you checked? (other than the spark)

On the 800 engine, it has a known issue with the pickup coil breaking from the mount. If it's cracked... it may be shifting enough to be cutting the ignition.
 
I had a similar problem with my 96GSX, turned out to be the voltage regulator. It's located next to the mpem in the front electrical box. To test it disconnect the red lead, take it for a ride, if the problem clears up it's the voltage regulator. Make sure your battery is fully charged because it will not charge with the red lead disconnected.

Lou
 
What have you checked? (other than the spark)

On the 800 engine, it has a known issue with the pickup coil breaking from the mount. If it's cracked... it may be shifting enough to be cutting the ignition.

Sounds good, and what about the rope issue? I heard or read somewhere that if you have something go through the impeller, and gets jambed ,it somehow throws the timing out ? Sounds odd to me but I'm new to this stuff. All was good till the rope incident.

Thanks again.
 
I forgot to mention that I've been through all the usual stuff like gas lines, carb cleaning, etc last season and, as I said, the thing was running awesome. No problem hitting 60 mph.
 
I would check the voltage regulator first, it's a PITA to remove the mag. cover.

Lou
 
what about the rope issue? I heard or read somewhere that if you have something go through the impeller, and gets jambed ,it somehow throws the timing out ? Sounds odd to me but I'm new to this stuff. All was good till the rope incident.

Not a chance. If the crank was that easy to throw out of index... the engine would eat itself.


(edit, I quoted the wrong thing)
 
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Hi Lou This is Slangford's son... i have the shop manual for the sea doo on my computer but can't seem to find anything about a voltage regulator... anyways i have the front electrical box opened up and im wondering if you could give me any more specifics... thanks
 
Hi Lou. This is Slangford's Son.. i currently have the front electrical box open and accessible... but im not seeing anything in the shop manual about a voltage regulator.. cont seem to figure out which red lead...... if you could give me some more specifics that would be very helpful... thanks
ChrisLangford
 
follow the yellow wires coming off the stator/magneto into the front electrical box. Those wire run into the voltage regulator
 
Interesting, let us know what you find. Some people figure out problems either from here or on their own and don't post results.
This maybe something I have to look into if carb cleaning doesn't fix the problem. Gl
 
My ski to will start fine and some days it seems to rev with no problem, others it acts as if its being flooded when you hit the go lever. I have replaced the lines, rebuilt the fuel selector, added a fuel filter been through the carbs and replaced the filters and such. Cleaned the rave valves replaced the water separtor screen too.

It seems that when you hit the gas it just bogs and will idle all day, It doesnt do it all the time thogh.
 
I can't say for sure but mine started doing the same thing last summer, at first it was a minor annoyance, I did a lot of the same things you did, finally did some extensive troubleshooting over the winter. Long story short it turned out to be the voltage regulator.

Lou
 
Yeh, Lou is on the money!! I've been reading this thread and thinking about my 96GSX and I just fixed it 5 min. ago. It would hit a rev limiter style wall around 3500rpm. It used to warm up and run right, but then it started to go into the fits even warm. I stopped riding that one lately because I can't have skis hesitating unexpectedly in tight creek corners. Well today I fired it up and it would'nt rev. I pulled the red wire on the regulator and it did! I had a used one in an extra grey box to rob(96GTX) and now I'm running perfect. When I was having this problem on the water I could trick it into running on high end this way: 1)shut off ski 2)pull throttle wide open 3)restart with throttle pinned and hang on. Of coarse in hindsight I could just have pulled the red wire. Thanks Lou
 
Thanks Fellas ill give it a try and pull the red wire and see what happens, I went back through my carbs when I didnt need to it sounds like!!!
 
The one in the EBay add was for a 720, yours is similar, it's got 3 yellow wires and one red wire. It's in the front E-Box next to the MPEM.

Lou
 

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Thanks Lou! Ill try it tommorrow, might make my family and neighbors mad if I fired the ski up at 11:15!!!!!
 
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