I have a 96 seadoo xp 787 let my dad put a battery in it and he put the little ground wire to the ignition coil on the positive post. After finding that out i discovered the coil has a big crack in it and i then replaced it. I have no spark now after new coil. I chack the white wire going to bottom of coil and its only showing 0.06v when cranking. The seadoo ran good during the summer but i know something is still messed up i get 2 beeps when putting key on nob as well
No spark on 96 xp 787
- Thread starter Bpjr3870
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Is the white wire on the + or - side of the coil? Did you get the plug wires pushed down into the replacement coil all the way?
AKnarrowback
Well-Known Member
I was thinking the same thing. My gtx did what you are describing and it was the small wire on the neg post, the crimp on connection flexed and snapped off.
Yes I connected the small black wire to the negative my father put that on the positive and burnt something up I checked all the fuses there are a total of 5 they are all good I did a multimeter from the negative to the bottom of the ignition coil where all the ground meat and I'm getting a good connection there I also put new bolts in that spot to get rid of the old rusty one I've literally check everything I even checked the new ignition coil to verify that it's working with a multimeter and the videos that I seen online to show you how they work and how to test them my multimeter is reading the same thing that they are getting I am at 100% loss it ran 3 months ago now just won't run with this problem that I'm having
Did you check the 6 prong pin connector on the Mag? The pick up coil not functioning properly will prevent spark. It could be totally unrelated and just a coincidence. Even if the pick up checks out OK, there could be debris stuck to the magnet or rust. If the pick up cannot verify the firing point, the engine will not spark. I fought this for a period of time on my 96 GTX which is in the picture. Good Luck !!
I didn't check that only because it was just running a month ago the battery was bad so I told him just to go battery in it and I'll pay him back so that's what we did and then the Box near the battery was smoking and figure out what he had done replace the coil and figured it would start right up but it must have hurt something else I don't think it would hurt the mag
How would I go about checking resistance I read somewhere that said if you check it wrong that it can mess it up. Also I follow the white wire back it goes to the computer that is inside the front watertight compartment could that have been messed up if so I'm betting on that because the white wire goes straight to that and that's the next thing after the coil
okay I just found a form online where you can test the mag if it's coming up between 160 ohms and 300 ohms the mag is good mine is coming up at 231 ohms so we know that that is good and I have a new coil so that is good the white wire that runs from the ignition coil to the front computer is not showing any signal so im thinking it's something in the control box up front any advice will be great I found two complete new boxes online Both are $279 just want to make sure I check everything before I go purchasing that
You still don't know if the pick up coil is working properly, I'm not saying it isn't. If it was mine, I'd pull the front cover off the mag and have a look inside. Don't go throwing money at these skis they will eat it up and still not run. Download a manual and to the proper testing of the MPEM and CDI. Take your time, measure 3 times... cut once. I have lots of spare parts for these skis... sometimes I change stuff I believe is bad and it isn't.
Sounds like you popped the CDI or the MPEM. Both of those are up front in the grey box. Usually it's the CDI but a MPEM can also cause a no spark issue without losing any other functions. Don't spend too much (over $200 total) because some people put big prices on that stuff. Don't fall for the aftermarket MPEM's because a lot of folks have had issues with those.
Major Woody
Active Member
Also worth noting that if the bracket for the pickup coil rusts away and it moves out of position, it will still test ok electrically but you will get no spark.
I would pull the mag cover and have a look before I ordered parts.
I would pull the mag cover and have a look before I ordered parts.
Naw this was a running ski before the incident. Not likely that the metal pickup support broke off do to crossing the battery.
I'm with ya Matt. Probably is the CDI and even the tests on those things don't prove much. 
Since it took me much time and research to find the problem with my very first 787, I kinda lean that way. You NEVER know what is lurking in the Mag area. This is a recent 720 I am working on. You just never know if the ski went under water or anything. My goal is longevity so I don't want surprises later on. I like to take a look that way when if there is a problem I know what it "isn't" and can look elsewhere with a degree of confidence. . LOL
Since it took me much time and research to find the problem with my very first 787, I kinda lean that way. You NEVER know what is lurking in the Mag area. This is a recent 720 I am working on. You just never know if the ski went under water or anything. My goal is longevity so I don't want surprises later on. I like to take a look that way when if there is a problem I know what it "isn't" and can look elsewhere with a degree of confidence. . LOL
Well I didn't think I needed to get this far into it but I guess I should have included this as well I rebuilt the entire motor 2 years ago when I first got it the oiler in the front on the crank wasn't pumping oil to the rear cylinder so I lost compression in the rear cylinder tore down completely bought 82 mm Pistons and rods I had the crank taken out and tested I bored over the cylinders to 82 mm because of the scoring left behind I had all that apart before and cleaned everything up and put it back together I went with a block off plate in the front and I just mix my oil now motor has Maybe 40 to 50 hours on it was literally running not long before I had my father put a new battery in it we had it running in the driveway with water I had to jump it with my truck after that I put it back in the garage and ask him if he gets time to replace the battery so he did and then put the negative wire on the positive and now the problem is happening
Well I sure hope it'd not the MPEM then. Or did you get the whole greybox? If so I hope it comes with the coded key and that is a good price.
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