1997 GP1200 65U won't rev past idle

[maxsimoneau]

Hi, just bought a 1997 gp 1200 65u engine with a no spark condition.
I know nothing what happened on that ski before me.
Firstly, Compression is good, i have spark on all cylinders , and carbs are getting fuel.

I replaced the stator by a brand new jet unit and still no spark.
I then bought a used 65u cdi and installed it. I now got spark and it started right away.
Starts and idle good but when I give it throttle , the rpms won't go up. Stuck at around 1800 rpms.
Feels Like there is an electronical cutout or protection.. i bypassed the temp sensor and there are no error codes or warning on the dash...

Any idea someone ?

try to buy a other cdi unit maybe ??

 

[smoofers]

Check the condition of your reeds. Very similar symptoms as what you describe.

 

[WFO Speedracer]

Ok here is where I would go next , very simple check , remove the flame arrestor top and the screen , crank up the ski , while revving up the ski hold your hand over the top of each carb , about an inch or so away , if you feel any reversion though the carbs yank the carbs and throw the reeds in the trash , I chased on of these forever with a similar issue , it turned out to be bad reeds, do not be fooled by how they look or if they look like they are sealing, if they were there would be no reversion back through the carbs, , I hope this helps .

Is it doing this loaded in the water , if so that is exactly what mine was doing , it wouldn't rev up and it would not make any power or plane out . On the one I repaired the reeds were so bad that the reversion through the carbs hit me in the face when I revved or attempted to rev it up , the reeds looked perfectly fine BTW.

 

[maxsimoneau]

Ok here is where I would go next , very simple check , remove the flame arrestor top and the screen , crank up the ski , while revving up the ski hold your hand over the top of each carb , about an inch or so away , if you feel any reversion though the carbs yank the carbs and throw the reeds in the trash , I chased on of these forever with a similar issue , it turned out to be bad reeds, do not be fooled by how they look or if they look like they are sealing, if they were there would be no reversion back through the carbs, , I hope this helps .

Is it doing this loaded in the water , if so that is exactly what mine was doing , it wouldn't rev up and it would not make any power or plane out . On the one I repaired the reeds were so bad that the reversion through the carbs hit me in the face when I revved or attempted to rev it up , the reeds looked perfectly fine BTW.

It is doing it unloaded, not in the water.
Here I made a video :

 

[WFO Speedracer]

Did you do the reed check I mentioned earlier ?

 

[maxsimoneau]

Did you do the reed check I mentioned earlier ?

Yes. I did not feel any reversion with my hands..
Still removed the reed to inspect. The first layer seems to be sealing but not the second layer... but don't know if that could cause my ski to NOT rev at all over idle rpms..

 

[Pro-pulsion]

Failing temp sensor? Any idea how many hours are on it? If it has 220+ then you might have an air leak at the crank seal from worn out crank bearings. I went through this mess with a couple of other skis and both times it was a bad crank bearing. Another easy test if you have access to the supplies, get one of those little handheld brazing torches and turn on the oxygen side only then apply the oxygen to the base gasket everywhere you can access and to the rear crank seal because it's not under a cover. If it revs up then you have your answer, either a bad base gasket or bad crank bearings. I went through all of this with an old seadoo and 2 97 GP760's. One GP was the base gasket, one was bad crank bearings, the seadoo was bad crank bearings on the mag side and allowed enough movement to contact the stator burning it out. It gave battery lights, hard starting both in and out of water but more so in water, and when it run, if you haused on it the battery light would come on.

 

[WFO Speedracer]

Okay a couple of things come to mind , but I still would not rule out the reeds ,First if you have a timing light or an inline spark checker hook it to one of the leads and watch the light if the ignition is breaking up it will usually show up that way.

While you are running the ski , what happens if you hand choke the carbs , does it pick up and run or not.

Those things are set up really lean and the flame arrestor and cover is very restrictive , with all of that removed it may be lean enough that it won't rev , it sounds like it is starving for fuel to me , but that's just my opinion , is this running stock jetting or has it been rejetted.

 

[maxsimoneau]

Okay a couple of things come to mind , but I still would not rule out the reeds ,First if you have a timing light or an inline spark checker hook it to one of the leads and watch the light if the ignition is breaking up it will usually show up that way.

While you are running the ski , what happens if you hand choke the carbs , does it pick up and run or not.

Those things are set up really lean and the flame arrestor and cover is very restrictive , with all of that removed it may be lean enough that it won't rev , it sounds like it is starving for fuel to me , but that's just my opinion , is this running stock jetting or has it been rejetted.

No it won't rev if I choke it, even if I prime it to get more fuel. I will try to check the timing or if the flywheel sheared the timing key.

 

[Jcary85]

Make sure you wired it correctly for the temp sensor. I believe it’s the pink wire off the CDI. It should be disconnected. Certainly sounds like a temp sensor issue.

 

[maxsimoneau]

Make sure you wired it correctly for the temp sensor. I believe it’s the pink wire off the CDI. It should be disconnected. Certainly sounds like a temp sensor issue.

Yes it is disconnected, as well as the low oil sensor. It really feels/sound like an electrical issue..

 

[Ryan Declark]

Shot in the dark, but I picked up a 550 once the entire lower end of the rw pickup line from pump to engine bay was plugged with dirt. Maybe someone lost a rag in the exhaust while trying to work on it previously. It does sound like either either starving for fuel or air, if you've ruled that out perhaps a restriction on exhaust flow is causing it to die out at higher rams.

 

[WFO Speedracer]

That CDI ran well enough to blow a motor all to hell but I am willing to ship another one out just to be sure it's not the problem.

 

[maxsimoneau]

That CDI ran well enough to blow a motor all to hell but I am willing to ship another one out just to be sure it's not the problem.

Thanks a lot.. really appreciate it !!

 

[Myself]

It's not the cdi if it has spark. I'm betting on the chinky chank stator you installed. Test ohms on the original, if it's good reinstall it.

 

[WFO Speedracer]

It's not the cdi if it has spark. I'm betting on the chinky chank stator you installed.

I would love to disagree here , for obvious reasons since I sold him the CDI box.

I did have a similar situation on an 1100 that turned out to be a bad CDI , at this point I want to be damn sure I didn't sell him a bad CDI box.

But I wasn't aware he replaced the stator with an aftermarket part either.

 

[maxsimoneau]

Just tried another stator. same problem...
really seems like a bad CDI ..

 

[Myself]

Just tried another stator. same problem...
really seems like a bad CDI.

.........."ANOTHER" stator?...........so....you don't have the oem original one?

 

[maxsimoneau]

.........."ANOTHER" stator?...........so....you don't have the oem original one?

Yup the orignal one that came from the ski makes no spark.. bought 2 other stators.
That ski seems like a big yellow lemon.

 

[Myself]

Well, it sounds like some proper troubleshooting needs done. Possibly the cdi COULD be bad.......so process of elimination would tell us. FIRST test battery voltage WHILE cranking. Many ignitions have a low voltage threshold and WILL NOT light off under about 10 volts...........including my riding mower LOL!!! MOST COMMONLY on older Yamahas, the kill switch goes bad. It can be ohms tested and/or unhooked to prove any difference to the spark. Next would be testing the stator ohms to see if windings are in spec. I also like to test a/c output voltage of the stator. Least common would be an ignition coil, again, ohms test primary AND secondaries. IF all of this tests good then I try a cdi.