red/black wire to bypass mpem for spark test

[Dr Honda]

I was reading in the service manual while I was supposed to be working… and I stumbled across something that may, or may not help you…but it does give a little insight to the system.

In the electrical troubleshooting section… one of the alarms is “4 long beeps” when the lanyard is connected, and the boat is in neutral. This error message is only on the 787 boat (yours) and it’s when the MPEM can’t communicate with the CDI unit.

First… are you getting this error?

Second, this tells me that the “Data” wire we’ve talked about is a true data line, and the MPEM and CDI “Talk” to each other. SO… the CDI on your boat CAN’T run as a standalone unit.

Third… are you getting any error beeps of any kind? Either in the normal system… or in the troubleshooting system. (press the button 5 times, and reinstall key, then press one more time)

I’m thinking you are going to need an MPEM unit. (Sorry)

 

[glenwhitt]

To the DR

I am also at work tracking my new cdi that is on a ups truck out for delivery now.

I do not get any errors when the lanyard is pluged in. When in nuetral i get the standard 2 beeps. I have power to all the fuses in the mpem and none have ever blown, since i owned the boat anyway.

I pulled the electrical box last night and pulled the mpem to get to the cdi. all the wires and electronics in this thing look brand new. Not even dusty.

Tonight I will try it with the new cdi box. If no spark after this I will set it on fire and call my insurance company

I put all the bolts back in the mag cover last night and bolted back in the motor mount. I was going to take the cover off and inspect but no way to get the 2 bottom bolts out without moving the entire engine back. Figured since I already have the new cdi comming i would try this before taking the jet pump and the water box out so i can scoot this thing back. will post after i get this in tonight. Thanks !

 

[Dr Honda]

Actually… that may be good news for you.

If you are not getting the long 4 beeps… then the MPEM and the CDI are talking, and since you get the normal 2 beeps… that tells me that the MPEM should be functioning. The CDI itself may not have any internal checks, and the firing circuit of the CDI could be burnt out because of a potently bad ignition coil. Also… since your trigger coil checks out… that eliminates everything but the CDI.

I have a good feeling that if you put in the new CDI… you’ll be back up and running.

Keep us posted.

Hey… just for shit’s-N-giggles… unplug the CDI from the MPEM, and plug in your lanyard, and let me know if you get the 4 long beeps. You'll be unplugging it anyway to plug in your new one.

 

[glenwhitt]

feeling better doc

This makes me feel better. I also spoke with the guys at MSD today. I been studying the docs and diagrams and found a discrepancy. They just sent me the correct instructions to use there 4255 to completely replace the mpem. I will loose the dess key part, but for the money......

Hope I do not even have to go down that road but if so at least i have a road to go down.

 

[glenwhitt]

no yet

New cdi arrived and i installed it. Still no spark. Tested with cdi pluged into mpem and without. Still get two beeps. I do have a new finding though.

With the wire harness unpluged from the mag cover/stator/trigger I get voltage to the white wire on the coil when cranking. Starts out fluxuating the settles on 7.8 volts. When this is pluged in I am unable to read anything with my meter. I was abel to get something last time around though with old ci in it. last time i was getting 11.3 volts at the white wire on the coil with power on and non cranking, and then when cranking I got .3. Now it is nothing with wire harnes pluged into mag cover.


Unpluged rev limiter and i get no voltage with or without the mag wire harnes pluged in so I do not think it is that. I am leaning now toward to the trigger since I do not get any voltage to the coil with the harnes pluged into the mag cover.

Any suggestions before I pull the jet pump and pull water box out to get the engine back enough to get the cover off?

 

[Dr Honda]

Well…

Since you don’t get the warning of 4 long beeps (which is specific to your boat) when you unplug your CDI… that points to a MPEM problem, but if you think you found a coil problem… check it out.

 

[glenwhitt]

MSD doc o replace MPEM

Yup. Looks like I will have to get into the stator and check things out. I did confirm the MSD 4255 can completley replace the mpem unit in a 96. I spoke with some guys at MSD and they sent me a doc that can be used with the doc on there website for the 4255. The one on the website wires the enhancer to use the mpem and keep the securty system. If you need to bypass the mpem then here are some additonal instructions;

Disconnecting the factory DSS lanyard security feature

Important: This modification will void the warranty and eliminate all factory electronics including the factory starter relay. You must also rewire or eliminate virtually all items in the stock electrical box.

Grey wire in 3 pin connector – Tachometer wire.
White wire from 3 pin connector – To new normally open lanyard switch.
Black from 3 pin connector – To ground stud or battery minus.

Violet from 6 pin connector – To fused battery positive–10 amp with all battery positive.
Black from 6 pin connector-To ground stud or battery minus.
Orange from 6 pin connector-To coil positive.
Yellow from 6 pin connector-To yellow/white wire from factory pickup.

Single green wire-To black/yellow wire from factory trigger pickup.

Single red wire with split-To fused battery positive-10 amp will all battery positive

Single tan wire-To coil negative

Note: The other side of your lanyard will be attached to the fused battery positive.

This will enable the ignition system to function without the factory lanyard. You will only be able to shut the ignition system off by removing the lanyard

Maybe this will help someone else with an mpem problem.

 

[glenwhitt]

Found a problem

New oem coil, $90.00. New oem CDI box, $278.00 (smokin deal). Hours and hours researching on the net, being told by tons of people "pull the mag cover and you will see the pickup broke off", priceless.

I finally slid the motor back tonight and pulled of the mag cover. Pickup was just hanging there. I have new stator with new pickup on the way now and will be here Friday afternoon. Hoping to have this back together that night and on the lake saturday.

Wasted time... I do not think so. I learn something every time and it takes my mind off the J.O.B. and my kids mom, who is in prison, again. Man can i pick em

Pics of the damage are attached. Will make final post Friday night saying it is running

 

[Dr Honda]

well... look on the bright side... you can sell the CDI if the coil fixes it.

So, the trigger coil checked out because it was still OK... but I guess it broke off it's base, and wasn't seeing the trigger point of the flywheel... Right?

 

[glenwhitt]

bingo

Thats it. Even though it ohm out ok with it not getting the signal from the magnets spinning by then no coil signal.

Was also told by a guy that a stator can still ohm out ok but not work. said a test not in the book was to do a voltage check while cranking the motor and you should see like 36 volts come out of the stator. Said it was ground and yellow/green wire. I am going by there friday to get my new staor with pickup and will ask what pin it is.

hopefully case closed.

 

[glenwhitt]

whats that u say

Going to the lake today? Oh ya baby! Got the coil pickup/trigger yesterday at 2:00. at 3:15 I had it in the cover, cover on engine, engine mounted back to mounts, water box installed, and electrical goods hooked up. Touched the sarter and she fired right up. (Used new rubber ring/gasket on mag cover also).

I love it when a plan comes together. And oh ya. for grins I wanted to see of I could measure the voltage on the white wire from the cdi to the coil after the repairs... I can. Was never sure of this before hand.

Looks like my treatment is over Doc

 

[Dr Honda]

glad to hear it. I wanted to hit the lake today, but they called for thunder storms. Guess I'll have to wait untill next weekend.

 

[glenwhitt]

was 100+, no clouds, no wind, at Canyon lake yesterday. Glad i had my spf 30 on for sure.

She ran like a champ yesterday. Better than it has in a long time. Any chance of this being loose for a while and therefore affecting the timing? One day I am 6,880 rpm with my nujet impeller (top end more than hole shot impeller) Next time out I have replaced pickup and while I had the pump out I put my SkatTrak impeller on (better hole shot). I am now pulling 6,970 rpm on glass. Before the new motor late last year I was pulling 7,200 with the nujet. Rev limit on this is boat is 7,200 and I was hitting it at WOT in the water. Don’t much think I will screw with it anymore though. I may take in to get it timed is all. It has never been timed since new motor/crank.

 

[seadoosnipe]

717 verses 787...timing?

This thread was very interesting to say the least. You two have worked hard on troubleshooting and finding the problem. I saw some steps that were omitted that I would have taken and some taken that I would not have thought of, so kudo's to not just a great job but a very informative thread. I enjoyed reading it.

I agree with you about the final results. There is no wasted time because the amount of information given and learned is priceless.

I'll put my two cents in now, for what it's worth. The 717cc engine can be timed. It's done by loosening the 3 screws on the armature plate and adjusting it slightly according to a timing light or stobe by marks made on the PTO hub.

The 787cc is a fixed system and is not adjustable by you. The only time the ignition timing might have to be changed would be when replacing the crankshaft, the magneto flywheel the trigger coil or the MPEM. Now, I know your saying, "well, I had to replace the trigger coil." This would constitute checking the timing. The only problem is, if you do, you'll need the MPEM programmer to retard or advance it. It's not able to be changed mechanically.

Great job and a really great thread!.........:cheers:

 

[glenwhitt]

Snipe - Thanks for the post. I hope the work we did on this may help someone else also.

Do you think it wise to take the boat to the dealer or repair shop to get timed with mpem programer? It thas not been mpem timed since I put the new hotrods crank in it last year. 37 hours on the crank now. Should I be able to pull more than the 6950 rpm with the skat swirl on? GPS reads 47 mph at wot on glass. Would like to be abe able to bump the rev limiter at 7200 with this prop. Shoul be close to 50 top end and a sweat hole shot to boot

Went to lake yesterday and was 97 degrees out. No wind and glass from 10:30 am to 3:00 pm then a little breeze picked up and she got a little chopy. No wite capes or anything so still very nice. Left the lake at 6:30 pm.

 

[nmpeter]

well here we are for part two of this same saga.. just picked up a 787 powered boat for a song..and no spark...Since about every wire to the ignition system has been cut and repaired, I'm going _right to the trigger coil_...who gets the case of beer if it's hangin in the mag cover?

the boat seems to have a fresh top end with a high compression head..I scoped the jugs and the pistons and wall look brandy new!.

the mpem post was gone and the wiring to them burnt, but I stuck the shop test post on there and was able to program a key.which allows the engine to crank.

This boat was somebodies darling back on 1998..but after ten years in the new mexican sun..she's looking a bit hagged out.

Funny, never read about a pickup coil breaking off in a 787 motor before and would have never considered it if the coil ohms out ok..which I assume it did since somebody who seemed to have some idea what to do had worked on this boat previously

 

[resmaily]

No Spark 1997 seadoo GTX

Hi,
Today i read all post and your problem till you got it fixed.
I am new in jetski and i bought mine 1 mounth ago, i took it to the lake last weekend and i tried to stat it up befor take it to the leak, it stat after afew carnk. then i shut off the engine and tooked it to the lake.

I think battry was week and i carnk afew times and died befor running.
i took it out and tried to jump it frome my truck, and it crank and start fine, but it died after afew second... (the engine was not running at the time i jumped it)

Then i bring it back home and checked the spark plug they looked fine to me but i chenged them and it get fuel when it crank (wet spark), but no spark,
Also i now th conector at meg cover is loss.

Do you think she may has same problem (pick up broke off)...
I live in San Antonio, texas i read you tooked your ski to Canyon lake then let me know if you are around...

New oem coil, $90.00. New oem CDI box, $278.00 (smokin deal). Hours and hours researching on the net, being told by tons of people "pull the mag cover and you will see the pickup broke off", priceless.

I finally slid the motor back tonight and pulled of the mag cover. Pickup was just hanging there. I have new stator with new pickup on the way now and will be here Friday afternoon. Hoping to have this back together that night and on the lake saturday.

Wasted time... I do not think so. I learn something every time and it takes my mind off the J.O.B. and my kids mom, who is in prison, again. Man can i pick em

Pics of the damage are attached. Will make final post Friday night saying it is running

 

[seadooya]

Hi,
Today i read all post and your problem till you got it fixed.
I am new in jetski and i bought mine 1 mounth ago, i took it to the lake last weekend and i tried to stat it up befor take it to the leak, it stat after afew carnk. then i shut off the engine and tooked it to the lake.

I think battry was week and i carnk afew times and died befor running.
i took it out and tried to jump it frome my truck, and it crank and start fine, but it died after afew second... (the engine was not running at the time i jumped it)

Then i bring it back home and checked the spark plug they looked fine to me but i chenged them and it get fuel when it crank (wet spark), but no spark,
Also i now th conector at meg cover is loss.

Do you think she may has same problem (pick up broke off)...
I live in San Antonio, texas i read you tooked your ski to Canyon lake then let me know if you are around...

They upgraded(bracket) in 97, but its possible. Using a light tester, have someone hit start button, while your probing the white wire at coil. If it does not light up, then yes, look into the mag assy and/or mpem. Make sure ALL grounds are clean...battery, at the coil..etc. If it does light up, then coil is to blame. BUT make sure, you check ALL fuses...mpem, electrical box...