1997 Seadoo XP start and sudden no start

[spoons]

Hey All,

I've got a 1997 Seadoo XP 787 that I picked up last year, used it a few times, then during the spring of this year I rebuilt the carbs, replaced the spark plugs and cleaned and rebuilt the RAVE valves or whatever they're called. I fired it up on the hose and ran it for 10 min or so without any issues.

Last week I hauled it to the lake a few hundred miles away, made sure i trickled charged the battery before the trip. Got to the camp site and connected the battery and fired it up on the trailer for 5-10 seconds to confirm it fires and made my way to the launch ramp. At the ramp, dead. All I get are the gauges when pressing the start/stop button but that's it.

Had super limited cell signal so my troubleshooting was very limited. I was able to confirm the starter cranks if I jump the solenoid but that's it. I get 12.7v at the other side of the solenoid. I checked the single fuse in the grey box and it was ok.

I then checked the fuses in the forward e-box which I believe is the MPEM, all ok.

Do I have a bad MPEM? Did my key lose its programming?

From my research so far, a replacement '97 mpem on ebay is $600+. Can I put in an MPEM from a '96 XP/SPX 787? I am technical but would need some sort of guidance or instructions.

I'd be grateful for any help or input.

Erik

 

[artr]

I would start by checking a schematic and see if the 12V and Ground lines to the MPEM are at the proper levels. As far as a 96 XP MPEM, the CDI was an external box and your 97 probably has the CDI built into the MPEM so they would not be compatible. Probably similar for the 96 SPX.

 

[mikidymac]

Sounds like your lanyard is not communicating. Do you get 2 beeps when connecting?

Also on the97' XP water drips on the MPEM connectors and causes corrosion. Bull the connectors and clean then put on dielectric grease and reconnect.

 

[spoons]

I would start by checking a schematic and see if the 12V and Ground lines to the MPEM are at the proper levels. As far as a 96 XP MPEM, the CDI was an external box and your 97 probably has the CDI built into the MPEM so they would not be compatible. Probably similar for the 96 SPX.

Ok thanks. I did find a schematic on this great website! I'll double check those lines this week.

 

[spoons]

Sounds like your lanyard is not communicating. Do you get 2 beeps when connecting?

Also on the97' XP water drips on the MPEM connectors and causes corrosion. Bull the connectors and clean then put on dielectric grease and reconnect.

I never got any beeps since i've owned it.

I'll pull both connectors this week and check for corrosion. I hope it's just the lanyard, we'll see.

 

[mikidymac]

The lanyard/dess are pretty difficult to diagnose without a working beeper.

 

[spoons]

The lanyard/dess are pretty difficult to diagnose without a working beeper.

Any idea where the beeper is located?

 

[Grim]

Any idea where the beeper is located?

They are mostly under the handlebar cover, on my 98 GTX it is there. They go bad often, but easy to replace and fairly cheap. If you don't already have it, DL the parts manual for your ski, it will detail all of parts and where they are located, makes it a little easier sometimes. You can find them free online.

I would take the buzzer off and test it with your 12v battery first, since you are having other issues in that area it might still be good and you may have a voltage issues elsewhere causing the buzzer not to work.

 

[mikidymac]

Yes, it’s under the handlebar cover.

 

[spoons]

I would start by checking a schematic and see if the 12V and Ground lines to the MPEM are at the proper levels. As far as a 96 XP MPEM, the CDI was an external box and your 97 probably has the CDI built into the MPEM so they would not be compatible. Probably similar for the 96 SPX.

How about if found an external CDI box to go with a 96 mpem?

The way I see it the 96 and the 97 both had a 787 so other than the electronics what stopping the 97 787 engine from running off the 96 electronics? I'm thinking I could muster up an entire '96 wiring setup off ebay cheaper than a 97 mpem.

 

[artr]

You would need to know that all the gauges, transducers, other electronic modules (VTS) and timing are the same for a 96 and 97. It might be difficult to check by part number because the connectors might be different even if the gauge/transducer is the same. I m pretty sure the connectors that attach to a 97 MPEM are significantly physically different from a 96 and you would have to hash that all out. If you fixed the beeper and get no codes probably the quickest way to get things running is to send the MPEM out for testing to be sure that is the problem.

 

[spoons]

You would need to know that all the gauges, transducers, other electronic modules (VTS) and timing are the same for a 96 and 97. It might be difficult to check by part number because the connectors might be different even if the gauge/transducer is the same. I m pretty sure the connectors that attach to a 97 MPEM are significantly physically different from a 96 and you would have to hash that all out. If you fixed the beeper and get no codes probably the quickest way to get things running is to send the MPEM out for testing to be sure that is the problem.

What if one doesn't care about the gauges or transducers? Will the motor run without them connected?

 

[artr]

The gauges and transducers are probably optional, but some sensors may be important if you want to avoid other problems (engine temperature, beeper, oil level low). I have a 96 GTX which is very similar electronically to a 96 XP. You would need to compare the 97 and 96 XP schematics and decide what is needed to make it run and how to connect it.