Really stumped with the '92 XP

[tomski]

I need some advice from an old school two stroke Guru who knows what I could possibly be dealing with... referring to the plug that plugs into the coil from the mpem.... when I have it unplugged it runs like it did two years ago like a champ!...but when I plug it in, it shuts down like I hit the kill switch... when it is unplugged and the ski is running ,I cannot kill the motor with the tether nor the kill switch... it's when I plug it back in it will shut down.... already tried two different kill switch.... the mpem has rectifiers on it... thanks for any advice

 

[tomski]

This is the plug that I am speaking of

 

[Matt Braley]

Check those replacement switches with an Ohm meter. The original switches in those older ones(start button) connect their 2 wires and then disconnect them when pressed. Then starting around 95 the start button switches connect their two wires when pressed. Most replacement switches out there are these later "normally open" style ones.

 

[tomski]

So I should be focusing on the kill switch (which i changed out with one from a parts ski with no change ) and the push button starter...i read another thread and there was something mentioned about having a rev limiter issue...??? This ski runs great ,I just don't know what could have happened during storage! ???

 

[jjsinaz]

Not sure if the 92 works the same way, but on my 94 GTS, the stop button was a normally closed (opens when pressed, as Matt stated) and the kill switch (lanyard) was normally open (closes when pressed by installing the lanyard). The idea is that whenever the lanyard is on and the stop button is not pressed there is a path from the MPEM to a ground post in the e box. On mine, if the lanyard was not on and you pressed the start button, the ski would not start.

That being said, if you can start the ski with the lanyard on, then the stop circuit is probably okay. I am inclined to think that your problem is the rev limiter, which is internal to the MPEM and you probably need a new MPEM.

If you haven't done so already, download the service manual for the 92 and look up the wiring diagram. Those wiring diagrams are invaluable when trying to troubleshoot electrical problems on these.

 

[tomski]

I know it's not recommended, but when I did have it running out of the water with the garden hose hooked up, I did punch it and I do not believe the rev limiter was activating like it should. .... again I only held it open for a second and did notice the rev limiter was not going to do what it should do....

 

[tomski]

I have this mpem I took off a parts ski ... the year on the label on the back of the mpem says '93, part number 278-000-413 ..this one has 8 wires the '92 has 9 wires as shown in the images... which one doesn't get hooked up?.. I've looked at different posts and some believe that it supersedes 278-000 - 020 / 070... 0

 

[tomski]

this is the other picture that didn't load for some reason

 

[jjsinaz]

Check this out

http://www.seadoosource.com/mpemref.html