2001 Seadoo 717, plugs fouling, either weak coil/stator? DVA test for the stator?

[SparkieBoat]

My seadoo keeps fouling out the plugs. mostly seems to be the rear one. It will run great one minuet then start running on 1 cylinder with the other one trying to kick in but then out again. I did a DVA test on the power going into the coil it was around 120 V. I know on an outboard it should be 150 plus. I am not sure about jetskis. Does anyone know what the DVA readings should be? Also how can I diagnoise a weak coil? If both of these are good, maybe too much oil??
Thanks

 

[SpitAndDirt]

Here is a download for a manual.

Things to try: Unscrew the spark plug caps off the wires, snip 1/2" off wire, screw back on. While you have the caps off, you can test each cap for proper resistance which should be about 4.48 Ohms for each cap.

You say that the plugs are fouling out? Have you cleaned your carb since you have owned it? Do you run pre-mix in the gas tank? Do you run Stabil through it before your store it? How long has it been doing this?

By the way, look at page 10-02-17 ---->The resistance should be 0.34 to 0.62 Ohms at 20C. for the primary side of the coil. The secondary side is measured with both spark plug caps removed. The resistance should be 12 +/- 3 KOhms at 20C.

http://www.seadoomanuals.net/downloa...hop-manual.pdf

 

[rvaughn704]

I doubt the issue is too much oil.
I also doubt you have a coil issue.

I agree with spitanddirt you need to start by cleaning the fuel system.
Like rebuilding carbs.

 

[SparkieBoat]

Thanks guys. this was very helpful. I am a bit ignorant about jetskis. I cleaned the carb already. I do not premix, but that was going to be my next project. It seems that either the stator or the voltage regulator are bad. When I crank the engine the battery reads the exact same as not running 12.5 V. So I assume it is either the regulator or stator. I did figure out that it uses a different coil for the ignition. I will do some testing and OHM reads. Thanks a bunch. That manual should be very helpful.

 

[SpitAndDirt]

Voltage regulators do tend to go bad on a regular basis on the older two stroke skis. It wouldn't be a bad idea to change it just because of it's age. Be glad that your regulator isn't part of the MPEM! Then it get's expensive! And yes, the voltage regulator can cause erratic running, I had the exact thing happen on my 1996 XP's.

 

[SparkieBoat]

thanks a lot Spit, I really do appreciate your help. I will go ahead and order a regulator.

 

[rvaughn704]

You can just unplug the rectifier and take the ski for a short ride to be sure that is your issue. It should be the Red Wire in the front electrical box. You will be running strictly off the battery when you do this so don' run it long. Just take a short ride.

 

[sixfigures]

Those engines are notorious for having leaks in the crank seals between the rotary valve compartment and the cylinders.
Does it smoke a lot after it sits for a week or so. If it does but clears out as it warms up you probably have oil leaking in to the bottom end and getting in the cylinders, also if you do premix you must have the oil tank and oil in it for the rotary valve as that gets it's oil from the tank.

 

[SparkieBoat]

Thank you six. yes it probably is leaking the oil. But it is not charging the battery. or at least it does not seem to be, volts are the same with the engine running as when it is not running, 12.5. I did replace the regulator, I am in the process of replacing the stator. I will let you know what happens. By the way; If I do not ground out the plug wires and turn the engine over what possible damage could occur?

 

[sixfigures]

it depends but it is dangerous to do that as any fuel or fumes can ignite from a spark especially any blow back from the crank case.
some say it can damage the coils etc.

 

[SpitAndDirt]

Thank you six. yes it probably is leaking the oil. But it is not charging the battery. or at least it does not seem to be, volts are the same with the engine running as when it is not running, 12.5. I did replace the regulator, I am in the process of replacing the stator. I will let you know what happens. By the way; If I do not ground out the plug wires and turn the engine over what possible damage could occur?

Continually cranking without using the grounding posts on the front of the motor will eventually cause the ignition coil to overheat and/or short out. The electricity generated in the secondary windings during cranking has to be dissipated somewhere. If the plug leads aren't connected by way of the spark plugs or the grounding posts, the energy that would normally fire across the plug electrodes to create a spark will now arc internally inside the coil windings breaking apart the coated magnet wire and cause shorting. It takes less than a second to use the grounding posts, they are there for a reason, though many people don't understand why they are there to begin with.