97 Challenger 1800 spark issues

[DnE1800twin]

I've been looking for a similar thread. I get a pulse at the white + wire on the ignition coil but no spark to plugs. I've trimmed wires. I tested coils. Both have 0.7 on secondary and one coil had 57 the other 33 on primary.
What should these coils produce on primary side. I'm guessing both coils are bad. Just wierd they both went out at the same time.
I have not looked into the mag cover just yet.
Any ideas?

 

[Waterluvr]

A regular meter won't work to test primary voltage, you have to use either a peak voltage meter or a DVA adapter to measure it. Stevens marine instrument offers a low cost adapter that plugs into most digital meter terminals.

If you're trying to test the resistance on the primary side of the coil it should read right at .6 ohm across the spade connectors on a good coil.

 

[DnE1800twin]

Both coils read .7 across the spade terminals. One reads .57, the other reads .33 across the plug boots.
I was going to replace the coils but it seems they are discontinued. Anyone know what part number to replace them with?
I do get a pulse with a test light at the white wire.

 

[Waterluvr]

So long as you don't see any visible cracks on the coil bodies nothing will change by replacing those, they should be fine.

 

[Waterluvr]

See what your getting from the trigger coil next, you can make a test plug for the mag housing using a 6 pin Deutsch connector & wiring to probe the right location:

 

[DnE1800twin]

Thanks for your help. I will try to get one of those connectors made up this week. I dont know much about the electrics on these boats but i keep goin back to the pulse at the white wire. Would I still get that pulse if the magneto or pickup was bad? Seems to me that if the magneto/pickup was bad then the pulse would not make it to the coil.
I was also told that maybe MPEM is bad. What are your thoughts on that?
Last season the boat was running. One engine went down and would not restart. Limped back to boat ramp. Got home and the other engine wouldnt start either. No spark at plugs.

 

[Waterluvr]

You can't assume anything with these ignition systems, one of the biggest culprits in a situation like you described are hot spots from bad grounds when you lose one and then another pretty good indication of some electrical resistance or circuit failure. I'd be taking the cables loose and ohming them end to end in addition testing the stator, trigger coil, neutral safety circuit, MPEM fuses etc. The MPEM module will give you a hard time if it's ground cable is bad, check that carefully for a bad end or any resistance at all end to end of the cable.

Are you getting two beeps when you put the lanyard on the post that indicates the MPEM is waking up, it sounds like it is and the motors will roll over? The digital portion of the CDI can fail in the module with everything else still in good order, you really have to run everything down with proper testing to figure out where the problem lies.

You might find the test plug you need at a scrap yard, I rent those things out and they have a bad habit of not making it back on time or ever two of my local yards keep a toy pile separate from the automotive stuff and I find harnesses all the time to snip them out of for a buck a piece beats trying to probe pins you can't see.

 

[DnE1800twin]

Good info. Much appreciated.
I do get 2 beeps. Though barely heard. I may need to replace the buzzer at some point.
I guess I'm gonna spend the next few days hunting and testing wires...lol

 

[Waterluvr]

Good info. Much appreciated.
I do get 2 beeps. Though barely heard. I may need to replace the buzzer at some point.
I guess I'm gonna spend the next few days hunting and testing wires...lol

Well that's very encouraging the mpem is at least responsive and you know the neutral safety is working, I'd really scrutinize the ground cables and ends Sea Doo used garbage cable in those boats I don't have a single regular boat customer we haven't changed those on by now and were strictly low hour short season freshwater use here in a salt environment it's a miracle anything works on boats with factory cables still in place.

If in doubt don't even hesitate to trim a couple inches off the bilge ends and install new connectors and make more tests, if things suddenly change rip that stuff out and replace it any new cable and ends is a huge improvement. Clean up all the coil and MPEM grounds really well and see if anything changes after you check everything else out.

I know a guy in Ocala that might have a spare used coil you could borrow, lemme call him and check it would be nice to have one on hand to try but it sure sounds like what you have should work fine with .7 across the spades.

That intermittent buzzer you have, I've got a bag full of used ones I keep for spares. Funny thing about those, most will work fine when I wire one direct to a battery yet they work 50/50 in a boat or ski and the replacement buzzer get's it back to working all the time in most cases when the grounds are tired.

If you run a new jumper ground wire direct from the battery to the ground on the buzzer and it suddenly starts behaving again that gives you some insight into your electrical system. If it's just old and tired and really needs replaced this is a drop in replacement from Radio Shack for about $7.00 works just as well as the Floyd Bell unit that was OEM.

 

[DnE1800twin]

Good to know.
If your friend in Ocala is Jim, i have his number and was gonna give him a call too. I know him pretty well.
I will be checkin all my cables and wires this weekend.

 

[Waterluvr]

Good to know.
If your friend in Ocala is Jim, i have his number and was gonna give him a call too. I know him pretty well.
I will be checkin all my cables and wires this weekend.

He (Rick) returned my call just a few minutes ago, seems he's fresh out of about all the 2-stroke parts anymore. I did find a loaner coil that's good, worst comes to worst I could send that to you to try good used ones are out there.

 

[biffdotorg]

Sorry guys, but I find this very ironic that this thread got started in the SeaDoo Spark Forum! And answered. What a great group of guys we have here! And nobody gave them crap about it.

Too funny! (it's a spark question)

 

[Coastiejoe]

Yep. It was a spark question. Close enough. LOL.

I totally missed that. I normally look early on so I can move it in the early stages of need be.


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