95 SPX Electrical Issues

[CorbinSeadoos]

When starting, what should the voltage going into the coil pack be? is it supposed to fluctuate? is it normally supposed to be 12Volts consistently going into the Coil Pack? If its not what it is supposed to be? does that mean a bad MPEM? because that's where the coil pack connections come from. would the rectifier have anything to do with it? Putting my multimeter in measuring the voltage going to the coil pack while starting the voltage jumps all over for me. It never really gets to 12 volts jumping between 4-7 volts. Is this correct or do I have a bad MPEM? I cannot find anything about the electrical system for a 95 SPX Rotax 657X anywhere.
Anything Helps,
Corbin.

 

[artr]

There is a shop manual for your ski at seadoomanuals.net. It has an electrical section that descibes the ignition coil and generating coil as well as schematics. I took a quick look and I think the generating coil is generating current pulses that drives the ignition coil that the manual says has an integrated CDI that would generate the high voltage for the plugs. I think the generating coil is also just an input to the MPEM.
Are you getting spark? If not the manual should have tests for the coils, stator and plug wires (usually resistance measurements).

 

[mikidymac]

These are CDI ignitions so the coils don’t work like older car coils as they don’t get battery voltage. They a more like a transformer boosting the voltage when the capacitors discharge.
You aren’t going to get 12v to them.

 

[tobytd]

Signal wire to coil should cause a test light to ‘flicker’ when cranking

 

[CorbinSeadoos]

There is a shop manual for your ski at seadoomanuals.net. It has an electrical section that describes the ignition coil and generating coil as well as schematics. I took a quick look and I think the generating coil is generating current pulses that drives the ignition coil that the manual says has an integrated CDI that would generate the high voltage for the plugs. I think the generating coil is also just an input to the MPEM.
Are you getting spark? If not the manual should have tests for the coils, stator and plug wires (usually resistance measurements).

Getting Spark but it doesn't start. I've changed out everything on the ski besides some of the electrical components so i was thinking maybe the reason it wasn't starting was because of weak spark or incorrect spark timing. The coil pack is one thing I replaced. The MPEM and Stator is have not.

 

[artr]

Do you know if it is getting gas. Try a little premix down each carb and see if it fires. Do you have the grey fuel lines? When was the last time the carbs were rebuilt?

 

[CorbinSeadoos]

Fuel lines have been replaced, I tried gas down the carbs and starter fluid the other time and still didn’t even sound like it was firing. Carbs haven’t been rebuilt but only run premium gas through them also checked the fuel filters in the carbs and they are clean.

 

[artr]

Did it ever run? If so then probably not the timing. Run all the resistance tests on the ignition coil, generating coil, stator and plug wires. Make sure your battery is charged and load tested. When was the last time the plugs were replaced? I don't think the rectifier would affect starting but you could disconnect the red wire coming from it to take it out of the picture.

 

[CorbinSeadoos]

Yes it ran but then the oiler cable broke and the engine seized up so I got the engine rebuilt and put it back in, now I cannot get it to start. I checked timing, carbs, everything mechanical. I resistance tested the stator and it checked out. I disconnected the red wire and still nothing. New coil pack, plugs, during all of this also. I have basically replaced almost everything in the ski by now, the only thing I haven’t replaced yet is the Rectifier, CDI, and Stator. I disconnected and tested the start stop button and it was good also. I’m at a dead end here on figuring out why it won’t start. Everything I can think of I’ve done or checked. I know it’s getting enough gas because I took the plugs out after trying to start it a couple times and turned it over with plugs out and gas came out of the plug holes. Engine moves freely by hand, and compression is good. My guess as of now is the stator is bad because there was something wrong with the flywheel when the engine seized up so I’m thinking maybe that could have messed with the stator it’s the original stator that I know of I might try replacing that next but I hate to stick time and money into it not knowing it will work. Thanks for your help.

 

[artr]

Maybe before replacing anything else check the timing according to the shop manual. Maybe it was not set correctly when the engine was rebuilt.

 

[CorbinSeadoos]

Maybe before replacing anything else check the timing according to the shop manual. Maybe it was not set correctly when the engine was rebuilt.

Double checked timing and Is correct.