94 SPi weak spark 587/580

[tmryan362]

My kids took out the old ski this weekend. During the ride the tuned exhaust pipe developed a leak (i think this was a common issue with this vintage ski) The ski took some water but did not flood the engine--although it had stoppred running shortly after the leak occurred.

When I got the ski back on the dock, it would crank but not start. Since the ski is 18 years old figured the problem was in the brain box (could have got wet when boat took on water)--Since I had another box from an identical ski (oil injection pump and toasted the motor) I swapped out the box, the old box showed some age but did not appear to have gotten wet.
After installing the new box I still had weak/no spark. If I ground the the spark plug I get a mild jolt not the zap you get with a good ignition system.

Battery is good, compression shows even compression at 130, did the gas down the carburetor trick--still nothing. Problem is spark.

Pulled the front cover off the flywheel- does not appear that water got in there.

For lack of better--could the stator be bad how do you test if stator is good?

Would appreciate any ideas to trouble shoot this problem--would hate to turn this ski into a flower pot.

Tom

 

[Coastiejoe]

Remove the plug boots and trim the wires back 1/4 inch. I doubt this is your issue as I assume both wires are producing equal results. But,,, if this had never been done it should help as they break down as the ski ages.

They unthread BTW.

 

[tmryan362]

any advice appreciated

 

[Minnetonka4me]

Open the ebox and unhook the blk/red wire going from the MPEM to the coil and retry. If it fixes the problem, your MPEM is going bad.

I know you replaced it, but thats the easiest test. If you find the same its likely the stator. Make sure to wiggle the crank when its all apart and make sure the crank bearings are coming apart. Alot of times the stator gets burned up from the crank wobbling.

 

[tmryan362]

Thanks for the help. will pull wire this weekend and get back to you. If it is the stator can I pull it in the ski without pulling the motor. I know I can pull the gas tank out since I had one of the tanks with a bad filler neck.

again thanks.

 

[Minnetonka4me]

If you got a good flywheel puller...thats the hardest part. That and not being able to see the screw holes.

 

[tmryan362]

ok, I pulled the red/black wire--not much change. minimal spark. I can ground the spark pug by hand and get just a mild shock--I should get a good jolt if everything was good.


I guess this means that the stator is shot. Right??? NO way to field test the stator?? I can only guess that when the exhaust pipe leaked enough water entered the flywheel housing that it got to the stator.

It looks like there may be enough room the change the stator in the ski. Has anyone ever done it that way??
Any "tricks' I need to know the change it.

The manual says a 30mm nut on the flywheel--does a 1 1/4 sae do the trick. does anyone know what size puller bots are needed for the flywheel puller, sae or metric? I assume that there are some type of alignment marks on the housing and stator??
I ahve the manual but not much info on this topic.

Thanks for any help. Tom