PLEASE Need Help with new MPEM

[One40ozBUICK]

OK here is my last post about this:

http://www.seadooforum.com/showthread.php?39755-1998-Seadoo-GS-Popping-Fuses&highlight=popping+fuse

Please read to understand. I just got a new MPEM with dess and rectifier. But I want to know what if any thing causes the mpem to go bad. I do not want to hook it up and fry this one too. Don't have the full history on ski cause I bought it with mpem blown. What should I do if anything before I hook it up? help!!!

 

[Dr Honda]

a few things cause an MPEM to go bad... and twice in the last thread, you were told to disconnect the VTS completely from the system. I read though the last post... and didn't see you responding with an "OK... I'll try that."

If you want help, you need to respond to the people trying to help.


SO....

1) Jump starting the ski from a running vehicle.
2) A shorted VTS.
3) hooking up the battery backwards


DISCONNECT THE VTS BEFORE PUTTING POWER TO YOUR NEW MPEM !!!!

If it doesn't melt down... check the VTS before reconnecting it.

 

[CodyT]

Chances are that its fried but still try disconnecting the VTS COMPLETELY! The MPEM is hooked up to the VTS "Computer" inside the main electrical box so it can cause things to go screwy... If that doesn't work go hunting for an e-bay special mpem. A lot of folks will blow a motor or wreck the ski and sell the working parts cheap.

No I don't believe you can rebuild the MPEMs, earlier models could scrape the sealant out and see the board but BRP now puts an additive in the goo which makes repair impossible...

Check your wiring! Use your meter to check resistance on all lines and be sure they are within manufacture spec. Never use fuses larger than spec... It was probably killed by someone trying to jump start it (check your solenoid as it may be why someone thought a jump would get it going). The MPEM can't handle more than a few amps and will fry like an egg, keep this in mind when charging as well. I use a 1.5a processor controlled charger.

 

[One40ozBUICK]

Sorry about not replying I'll remember to do so in the future. I went out to look at or for the VTS but could not see it. I looked on the manual and I'm sure I'm gonna be wrong but it looks like the GS didn't come with it...? I just couldn't see any thing that resembled it on the ski. Is it there and hidden? Only electric connection I see is the rear electric box with a 15 amp fuse in it and plug wires go into it. help!

 

[Dr Honda]

I'm sorry... we had you looking for something that wasn't there. No... the GS didn't have the VTS (power Trim) system. The GSX did.


OK... so, why did the MPEM give up???????????


Hummm.........


Well, going to my response above. Most likely, it was from the last owner jump starting the ski from a running vehicle, or trying to start it while hooked up to a charger. Then, the problem was made worse with the big fuses.

Your electrical system is very simple, and only has a few things in it.

I would disconnect the gauge(s) from the harness, and check them individually. Also, I would look for any chaffed spots in the wiring harness. (possible short) Lastly... if a single part (other than the old MPEM) shorted out... give them a sniff. Burnt/shorted electronics have a very distinctive smell of plastic and charcoal.

 

[One40ozBUICK]

I'm new to these but I figured as much. I looked at everything and so far everything looked ok. No burnt smells or burnt wires. Also curious about the stator, I've read in a few post that pieces fall off and short it out. Could this apply to mine? Should I pull it out and inspect? The replacement mpem hurt the pocket book so don't want to chance it? I'll wait for a reply on this stator thing before I connect my new mpem. It's getting warmer here in the So Cal desert and the Colorado river is calling!

 

[Dr Honda]

Yes... the stator can short out... but it shouldn't short out the MPEM since it's isolated via the regulator. The normal issue with a shorted stator is that your charging system gives up. NOW... if you regulator goes bad... it can feed high voltage to the MPEM... but that normally doesn't kill it either. (not at first)

If you want to check that... open the connector at the engine, and check across the yellow wires with an ohm meter. You should have some resistance... and you should not have a connection to ground. If you see a ground... then it could be bad... but that won't short the MPEM. Once you get things running again... you can disconnect the red wire of the regulator, and check the output. (should be around 13.5 to 14.5 volts)

 

[One40ozBUICK]

Ok... I hooked up the new mpem. No fuses popped. But still no beeps? It does crank over good but didn't start. Battery was low so I'm charging it now. It hasn't ran for a while so I'm hoping its a fuel problem. I can smell the stale oder of gas in it. Shuold it beep as soon as I connect my dess key? Battery died before I remembered to check for spark.

Update: I went in looking for the buzzer as other post described to do. Could not find it. Is it in the steering column / handle bars? I did find the two wires that go to the buzzer cut. Purple and tan wires. The ski has aftermarket Renthal Handle Bars and no pad cover. Is this where it would've been? I'll look to see if it sparks soon. Do my carbs need to be taken apart and cleaned?

 

[One40ozBUICK]

I charged the battery and checked the plugs. It sparks. Plugs were gapped at about .025 in is this correct? I'm guessing I need to clean my carbs now from sitting fuel.

 

[IDoSeaDoo]

Yea, the buzzer is typically in the handle bars. If you found the wires cut, you can probably order another one on ebay for pretty cheap. If you've got spark, and compression, sounds like you just need to deliver fuel. If you haven't rebuilt/cleaned the carbs in a long time, the internal filters could be gunked up (especially if you still have those miserable gray fuel lines -they fall apart and clog internal carb. filters) These Mikuni carbs are relatively simple to go though and clean, rebuild kits are pretty cheap too. You can always pour some gas down the carb throat to see if it fires (be careful doing this, don't start a fire).

 

[One40ozBUICK]

The motor hasn't beet touched so everything is original including the grey hoses. I removed the carb (boy are they serious with the Loctite) and truthfully it looked like someone poured maple syrup in the carb and lines. Bad gas since it skipped a couple seasons without being used. I'm cleaning it out and the lines too. Sux cause there is a full tank of gas in it. Question: Does two-stroke oil (premix) do bad? Should I drain that one too?


Update: Once the carb was taken apart the inside was clean as can be. Checked all ports & screws all but accelerator pump. Would not come apart even with screws removed and don't want to pry open and damage it. I does however sound good & strong when pumping. The inner filter screen was full of debris (problem?) could it be lines are clogged?