1997 Seadoo XP MPEM

[skiweb01]

Hello,

I just picked up a seadoo xp 787 1997 for cheap with a trailer since it was hydrolocking with oil in the PTO cylinder. I was able to get it running today off starting fluid, put it in the water and let it run for a while to burn out the oil. It worked pretty well and the ski restarted over and over again without hesitation. So I might be able to put off taking the crank apart for a few years.

However, I was riding the ski around to get out any more oil and it all completely shut off, no power to anything. Took it home and tested all the electronics and determined it was was the MPEM.

I know that it is becoming more difficult to find 1997 seadoo XP MPEMs and I really don’t want to spend over $500+ for a used OEM MPEM. Is there anyway I can use a different MPEM (ex. 96 xp) or do something else to get the ski running. The trim doesn’t work so I don’t care if I lose that and if I have to lose the gauges that isn’t the end of the world for me.

All I really want is to get the jet ski running again for a not so steep price since I know a new crankshaft might be in the works in a year or two. Any suggestions? Thank you.

 

[Matt Braley]

Yes you can run it off a 96 787 grey box but you will have to wire it in yourself. The wire colors are the same and coded by function. To run you need:

3 wire to the DESS post (and a key coded to the 96 MPEM)
2 wire to the start/stop switch
3 wires to the black e-box (not tan)

Obviously you can keep going for gauges, trim, etc. but that's what you need to run

Look over the plugs to your existing MPEM for corrosion. Many times it's still a good 97 MPEM but there are bad connections on the pins.

 

[mikidymac]

I totally agree with Matt B.

The 1997 XP is notorious for corrosion on the two MPEM plugs. I suggest DeOxit for cleaning them, it’s very common.

Also I suggest making sure you are running the correct API-TV full synthetic oil and rebuild the carbs with only genuine mikuni parts.

 

[TrevorM]

Interesting read as I too purchased a 97 Seadoo XP and am in the process of doing some maintenance work. I like the suggestion of checking out your MPEM connections and cleaning them. My previous 01 GTX would randomly shut off with no power whatsoever and I cleaned the dess post/key and cleaned every electrical connection and that solved my problem and fixed my gauges! I plan to clean out every connection on my 97 XP just in case of any corrosion. Best of luck!

 

[mikidymac]

The 1997 XP has the MPEM in the nose where the two air vents let water fall directly on it. Once Seadoo realized this was an issue on the newer XP Limiteds they moved up high on the side of the engine compartment.

Clean the plugs really good with DeOxit then use lots of dielectric grease on them. I have also made water deflectors for the plugs out of motorcycle inner tubes for added protection.

 

[skiweb01]

So I’ve pretty much tried everything, took it to a friend who works on stuff like this all day and he confirmed that it is fried. I’ve been looking online and found a new WSM MPEM for the 97 xp. I was wondering if anyone has had experience with the WSM MPEMs and how they are. I found a new WSM for the same price as used OEM ones. Any idea of the difficulty of programming these WSM MPEMs and how they hold up? Thanks.

 

[Matt Braley]

I have not heard too many good things about the aftermarket ones. I had one acting sporadically that eventually quit making spark. Normally I'd say used OEM all the way but 97 is the worst year for 2-stroke MPEM's. Maybe you can find a nice clean one around $300 because the season is coming to an end soon.