97 Speedster, no spark starboard side

[Jsimmy]

I stopped fast and the starboard motor died and wouldn't start back up. Port motor was unaffected. Limped in, pulled plug wires, no spark. Pulled plug wires off port side and put on starboard plugs and the engine started. IM stumped. Any ideas why no spark through starboard side plug wires?

Thanks folks!

 

[Gamerse]

Not sure how you could run the starboard engine with the port sides ignition system (seems impossible without swapping the magneto connection as well). Check the connection to the starboard coil inside the grey box. If it is good, try disconnecting the Black/Red/Green wire from the mpem to the coil. You will not be able to stop the engine using the start stop button with that wire disconnected, so be prepared to short the coil wire to ground, or unplug it with electricians pliers.

7.Ignition Magneto
The magneto produces the power for the ignition system, completely independent of the
charging/battery system. (not counting the shared ground) The Mpem controlls ignition by
grounding the generator and ignition coil.
A.Measure the black to black/red/green (starboard side magneto plug) wires. Ohm meter should read 40-76.

Mpem troubleshooting guide is now stickied to the top of this forum.

:cheers:
Ernest

 

[Jsimmy]

So I'm getting a multimeter today and will check the Ohms mentioned in 7A. Is there a way that a resistance check could also tell me if the coil or the MPEM itself is bad. I guess what I'm asking is where should I work back from? Or should I start from the MPEM and work towards the spark plugs? I hope this makes sense to you. It makes perfect sense in my head :willy_nilly:. Thanks for your response!

 

[Gamerse]

I would check the black/red/green wire as mentioned above. You can swap the coils electrically to test them since you have two identical units, and one works.

:cheers:
Ernest

 

[Jsimmy]

I'm on it. This will be my first foray using the multimeter. It seems easy enough, but any tips you can give me on making sure I'm doing it right would be great. I'll follow up with results from the test.

 

[Jsimmy]

Okay, I apparently thought more of myself than I should have. Could you tell me, in relationship to the two coils (they're black right), where is the magneto? I could not find any black/red/green wire anywhere inside the gray electrical box. That being said, I did NOT get to check that wires resistance. Thanks.

 

[Gamerse]

Its cool, don't beat yourself up. There is a small wire going to each coil. This is the same wire that goes to the magneto of the respective engine. Follow the spark plug wires to figure out which one you are working with. The same wire going to the coil will also go to the mpem. Unplug it if it has a connector. If it does not have a connector, you can test the coils by swapping the small wires from coil to coil, and seeing if the system that is working, still works with the other coil. I'll go into more detail as you figure out more.

The magnetos are behind the flywheels in the front of your engines. The square connector on the front of the engines is where you would test the magnetos.

:cheers:
Ernest

 

[Jsimmy]

I'll get on this after work. One other thing though, in the service manual for my boat, it says if an engine turns over but won't start, you could have water in your fuel line or fuel filter. I think this could be a definite possibility because I was driving around without my drain plug out (I didn't realize until after we pulled it out of the water) and there was a lot of water in the engine compartment. And, it looked like there was a section of the gas line where it tees off to go to the other motor that was completely submerged. I don't know why this would cause no spark, but do you think water in the fuel line/fuel filter is a possibility?

 

[Gamerse]

Unless you water fouled a the plugs, or a drowned stator assy, I don't think that it would cause no spark. You can try removing the front engine cover of the non-running engine and inspect for signs of water. It will probabbly still be wet, if there was water in there, at that point. You could swap plugs to see if you need new plugs.

:cheers:
Ernest