No Spark - 99 GTX Limited

[rtreverton]

Problem: No Spark!

I have read many of the posting regarding troubleshooting no-spark problems and have tested everything I can think of or have read about. I even took my boat to the dealer and had them try to narrow the problem down so that I could fix the boat myself. The dealer feels the problem is the trigger coil. I replaced the trigger coil and still do not have spark.

Here are the things I have done to try and resolve the problem;
- tested continuity in all wiring and connectors related to the ignition
- replaced the stator and sensor coil
- cleaned and tested all grounds
- replaced spark plugs
- exchanged the MPEM with known working unit (dealer did this)
- checked all related parts and curcuits with ohm meter (dealer also did this)
- checked battery voltage
- trimmed plug wires and re-capped

What I have not done yet is have the dual coils dynamic tested. It seems unlikely that both coils would fail simultaniously - but I guess anything is possible.

Any additional suggestions would be greatly appreciated.

 

[PaulS]

Does this have a CDI module if so I would place my bet that its shot,,
Ive had the same with a Ski of mine,,,,the CDI was a seperate module and was bust thought it did cost me $500 to replace

 

[rtreverton]

Thanks for your response. I think the MPEM performs the same functions as the CDI in older models. I had the dealer replace my computer with one from a functioning boat and I still had no spark.

Rob

 

[seadoosnipe]

Not quite?

The CDI, which is the Capacitor Discharge Ignition system and the MPEM (Multi Purpose Electronic Module) are two different pieces of electronic devices used in a primary way for all systems equipped.
The CDI, single generating coil system is equipped with the magneto, the ignition coil with the integrated ignition module and the MPEM.
The CDI, double generating coil system is equipped with the magneto, ignition module, ignition coil and the MPEM. The CDI is directly related to creating the electrical current needed for spark and the mpem is the brain that tells it that it's ready for it to do it. There are several functions of the MPEM. It has the rev limiter, the delay timer, and controls the iginiton systems limp mode when needed.
I hope this helps you in some way.

 

[PaulS]

Hi there,,
Here is the testing for the CDI module ,,chech the white to black as this is the feed to the coil that will give you a spark,
+ Meter Lead - Meter Lead Value
RE/PU BK 2.6 kOhm
YL/WH BK 0.380 Mohm
WH BK 2.208 Mohm
BK/OR BK infinity
BK/GR BK infinity
BK BK 0.2 Ohm
WH/BL BK 30.38 kOhm
BK RE/PU 2.690 kOhm
BK YL/WH 0.390 MOhm
BK WH 2.2 MOhm
BK BK/OR infinity
BK BK/GR infinity
BK BK 2.69 kOhm
BK GY/WH 33.07 kOhm
Give it a try and let us know how you get on,,,
Regards From Ireland,,,,,Paul

 

[rtreverton]

It is great to have a support group available to help me resolve my problem. I should have engaged this forum mid-summer when my boat first quit working.

I appreciate the responses so far and am doing some research before posting new information. Hopefully I won't sound so inept.

First, Louis/seadoosnipe - thank you for correcting me on the functions of the CDI and MPEM. After reading my shop manual for my 1999 GTX Limited, I found that the boat is equiped with a DC-CDI system which is integrated into the MPEM. The DC-CDI receives the input from the trigger coil and signals the ignition coils to fire. My dealer was able to test a working MPEM in my boat to determine if the computer (MPEM) was the cause of the no-spark problem. There was no spark even with the known good MPEM. So I replaced the trigger coil to see if that was the cause of the no-spark condition. Still no spark! Like I mentioned in my first post, I have checked all of the related wires and connectors including the ground wires and they all seem good.

I pulled the ignition coils, there are two for this boat, and I am trying to find somewhere to have them tested. Wouldn't it be a coincidence if they both failed at the same time?

If anyone can think of something else I'm missing I would appreciate your input.

Paul, it's cool to hear from someone all the way from Ireland. Doesn't the Web make this world so much smaller. Thanks for your testing information. I believe that switching out the MPEM point to something other than the DC-CDI.

Rob

 

[seadoosnipe]

Reading is fun!

Ron, I'm at work at the present moment, but tonight, when I get home, I'll go back into my manual to look for the test on the coils. I know there is a way to test them and I do agree with you. It would be coincidence that they both fail at the same time.

 

[PaulS]

Hi All,
Looking at all that has been checked the only thing left I can think of is a damaged wire in circuit ,,,,have you traced the loom and checked for an open ???
Regards
Paul

 

[rtreverton]

Hi Paul,

I originally pulled the entire wiring harness out of the boat and checked it for damage and checked continuity on all ground wires and power wires and all wires related to ignition and charging. I did this check while wiggling the wires to see if there was a possible break with an intermitten break. Also, I have checked and rechecked the related wires and connections in the boat...unbelievable that I haven't found the problem yet. I know there are not many components of the ignition circuit, so this problem shouldn't be so complicated. I may have to pull the harness again and start from scratch.

Still open for your thoughts.

Thanks again,
Rob

 

[rgpbeme]

just for limiting sake did you check the fuses with a meter. The 5 or 7.5 amp fuses on the board or the relay will kill the spark check both

 

[rtreverton]

Hi Louis,

Here are the specs that I pulled from my shop manual and the actual readings I am getting:

Primary Winding 0.29-0.30 ohm (actual .2)
Secondary Winding 7.6-11.4 kΩ (actual 9.4-9.6)
Spark Plug Cap 4.48 K ohms (actual 5.82-6.07)

Rob

 

[rtreverton]

Thanks for the suggestion. I have replaced the fuses a couple of times.

 

[seadoosnipe]

Good!

Rob, your test looks good and everything is within limits. I would rule out that there is a problem with the coil. The results on the cap are just a wee bit high but with resistance breakdown over a few years of use will show a little wear in the carbon element that directs that voltage. So, if anything, you'd have fire. It could be a little weak but you should have fire.
Have you checked all your grounding wires?

I'm off tomorrow so I'll be sure to pick your post up first thing in the morning and go over what you've done so far and what else can be checked to look for a reason as to why your not getting spark. It's probably pretty simple. These dag gum things got so many safety devices and sensors on um that it takes an I & E technician to figure them out. Look for me tomorrow and if by some chance, re-post. When you make a reply, it comes back bold in my forum, which are the first ones I always look at first.........
Till then, good night.

 

[kustomkarl]

Rob,from what I see in the posts it might be the mag/flywheel is corroded. I had a similar problem in a stand-up Jet ski of mine. All the componets checked out ...pulled the mag/flywheel cover and inside was full of corrosion and all kinds of nasty. The rubber gromet that sealed the wires entering, poped out and allowed in the nastys.(doing those 10 seconds submarines didn't help much either)
Karl

 

[rtreverton]

Louis,

Thanks again for your attention to this problem. Yes, I have checked the ground and cleaned all of the contacts as well. I agree that it's probably going to be a simple cause when the problem is found, because there really isn't a lot to this circuit.

Karl

I also was thinking that the flywheel could have been a factor, so I removed the cover again over the weekend. It is just as clean and shiny as new. No foriegn materials or shavings, no rust or any other gunk.

Hey...here is a lengthy chronology of the events that have led up to this problem. The full description may spark some ideas that I haven't thought of yet.

Back in the mid-summer my boat stalled out a few times during idle in the lake but started right up and ran fine. A week later or so, I couldn't get the boat to start, so I replaced the plugs and it still wouldn't start. After repeated tries I took the boat to the dealer. The dealer called the next day and said they replaced the plug (the ones I put in were new) and the boat was operating fine. Than one day my son took it out and after running (probably very hard) for 20 minutes or so, it shut down and wouldn't start. I found the front 5 amp MPEM fuse was blown. I replaced it and it started up again and seemed to operate fine. My son took it out again and blew the fuse almost immediately. I replaced the fuse and it would start but blow immediately. After replacing it again both the front 5 amp fuse and the back 15 amp fuse blew ( a couple of times). I took the boat to the dealer. They figured the problem was a result of a bad MPEM ($800). I found one on ebay and that still didn't solve the problem. I took my original MPEM back to the dealer and they put it in an identical boat they had in the shop. That boat started up fine. So...I continued troubleshooting and checking the wiring and grounds. I pulled the mag cover and checked the stator and sensor. I found a small piece of steel about 3/16" x 3/16" x .50" lodged between two of the windings on the stator. Couldn't determine where it would have come from. When I remove the piece of steel and reassembled the cover, the boat would turn over just fine and no fuses have blown since. Again after some continued troubleshooting and no spark, I took the boat back to the dealer and left it with them for a few weeks until another Gtx Ltd came in. They pulled the MPEM from that boat and tried it in mine but still no spark. The dealer assessed that even though the trigger coil ohmed out, it must have been bad. That's when I replace the trigger coil and still no spark. And so here we are. You have the details of all that has taken place and what I have done to resolve the problem. Oh...and the battery was new at the beginning of the season too! One other thing strange happened - after the first time I took my original MPEM into the dealer and they fired up the other boat, the gages now come on and stay on as soon as I plug the MPEM in. However, the lanyard still beeps twice and the starter will function properly.

Way too much information but it may spark some new ideas.

Thanks for your patience,
Rob

 

[seadoosnipe]

Fuses

Rob, sorry couldn't get right back to you earlier....wifey had me do some honey doo's.....(painting the kitchen cabinets.....yuck!)
Anyway, the fuses are there to protect the mpem from surges and any external grounding. The mpem going out is usually attributed to mis handling, or doing electrical test on it improperly.
I agree that your problem is not going to be in your mpem. The only thing I have'nt seen you talk about in your post was checking your rectifier/regulator. The mpem's power source comes directly from the battery. The magneto makes high voltage AC electricity by way of electromagnetic current. This current is then channeled through the rectifier and converted to high amp, low voltage DC power. The fues to your mpem could be blowing due to the rectifier not converting this power field correctly. This should also cause some battery problems and over the long run, starter problems.

The following is information from the shop manual.
Magneto output is 180 watts @ 6000 rpm. It produces 0-40,000 volts AC. Part of this current is rectified and regulated for use in the charging system.

The purpose of the trigger coil is to signal the engine position to the MPEM. The rotor has two protrusions 180 degrees apart that accompolish this signal to the mpem.

The mpem (multi purpose electronic module) is responsible for the interpreting information, distributing information, start/stop functions, the hour timer, the DESS (digital electronic security system), ignition timing curve and the rev limiter. The DC-CDI (digital direct capacitor discharge ignition) system is built within the mpem.

Every half revolution of the flywheel, a critical point occurs when the position of the magnets change changes the polarity of the current, flowing from teh generating coil. The CDI module detects the change of polarity and signals at the right time , the primary winding of the ignition coil to send power. The secondary winding steps up that low voltage current to create a spark for both spark plugs.

Two seperate ignition coils receive the input from the mpem, each coil will send high voltage to it's corresponding plug.

There are several test for your electrical system, static and dynamic, that will help you isolate, locate and repair this system yourself, with little experience. It seems all you have to know is how to read a manual and a multimeter.

I can't go into any more detail than I have due to the length of time it would take to type all the necessary information. If you have a manual, then you should be able to find all this information under the electrical section. If not, I suggest you become a premium member and getting the full benefits of use of the manuals and one on one help in resolving your problems.

 

[kustomkarl]

Rob,
lots of info to digest and a long technical reply from louis with some facts of the electronics. Looks to me from your problem info it could very well be the rectifier. If you don't have a manual you should get a copy from the premium section and do some electrical testing with a multimeter. If you haven't done much testing with a multimeter, read through it first and you'll see it is not that hard to diagnose. If it seems intimidating, just take your time and with some patiance you'll be ok. Process of elimination of the componets.
Karl

 

[rtreverton]

Louis / Karl,

You guys are great and very patient. I appreciate all of your responses and suggestions...even if I don't get this problem resolved here, I will go away with a great deal of technical knowledge. As far as the rectifier goes, I also thought that may be the problem and unfortunately in this model and year the DC-CDI, regulator and rectifier are all integrated into the MPEM (packed away for noone to see). Therefore, the change out of the MPEM seemed to elliminate the rectifier as the problem here. That's the reason I stated that this ignition circuit is not overly complicated since it should only involve the MPEM, trigger coil, ignition coil, and related wires and connections. MPEM - checked, trigger coil - replaced, wires and connections - checked, ignition coils - not yet qualified. I'm seriously considering buying new coils as a last resort.

What do you guys think?

Rob

 

[kustomkarl]

Rob, it appears you have turned over a lot of the stones so to speak. It seems like you've checked all the components vitial to fire the plugs. I re-read the posts from the beginning to see if anything got missed. It just might be the ignition coils, but I'm not sure if they would have caused the blown fuses. I've seen the regulator/ rectifier spike the circuit to blow fuses before, but this one has me stumped. I'm going to do some digging to see if I can't figure this out.
Karl

 

[rtreverton]

No luck yet!

Hey Louis / Karl,

I could use your feedback or that of anyone with experience with my seadoo model. Today I replaced the two coils and plug caps with new ones to add to the new trigger coil and stator. Still no spark...%#*!@$.

Here is a questions that maybe someone can answer. Should the coil mounting bracket have a direct ground? Right now, the black wire from MPEM pin 3-17 is fed through the connector that plugs into the back electrical box. That black wire connects to the coil plates and the coil bracket with another black wire from the seloniod. However, the coil bracket and consequently the selonoid are not directly grounded until the start button is pushed to activate the starter. This doesn't seem right. Should the coils be directly grounded?

Let me know what you think,
Rob

 

[rtreverton]

Here we go again...

I was checking for a ground connection before connecting the lanyard. Once it was connected, I was getting a ground reading. Back to the drawing board. I'll be back!!!!!

 

[seadoosnipe]

Coil mounting bracket?

I'm still hear and trying to make some sense into this situation still. On your last post, you asked about a direct ground from the coils.....no, there isn't. On the two coils, you have a white wire on both, one going to #3-18 and the other #3-19 on the mpem. Then the two wires that go from the coil to the plugs.
There is a ground wire coming from the mpem to the solenoid, which also looks like it has an engine ground too.
At some point, I would think the coils need their power wire and some type of ground. Therefore, the bolts that hold the coils on probably also double as an engine ground. Since the negative cable to the battery grounds the engine.
Let me know what your checking on next. I'll try and keep up a little better.