93 Sea-Doo xp rotax 657 will not start

[shawnmstout]

Hello, im new to the jetski world but not new to the electronics world.
I just bought this jetski today but i got a really good deal on it so i couldnt pass it up.

First I believe I have a bad silenoid but I am not sure what the outgoing voltages are supposed to be on the posts, checked the switch and its good.

Jumping the silenoid does make it crank but it does not start. Does this mean its a bad starter also or is there something else i can test. Might i have to replace the whole mpem or is there further voltage testing I can do. Thanks in advance

I need to know what model schematic i should be looking at.

 

[seadoosnipe]

Jumping posts....

When jumping the post on your soleniod, you will get the starter to engage the engine and spin it over. Good way to make sure the starter or bendix isn't causing any problems. But, without the mpem being signaled to supply power to your ignition system, you'll get no spark for ignition.
Your model number ski is the 5852 and your electrical drawing for the ski is on page 7-01-5 and is a very simple and easy to read drawing.
You should be receiving 12 vdc to the starter, at the post where your red wires are, 12vdc.
If your 5 and 15 amp fuses are o.k. in the electrical box at your mpem, then your problem is most likely going to be a bad switch, either on your stop switch, which is normally closed, the Tether cord, which is normally open, or your starter switch, which is normally opened.
So, go look at your drawing, do continuity test on those switches (I'd test for open and closed circuits) and then, make sure your electrical box fuses are also good.
You know the starter will spin over while jumping. Don't do that anymore. Although it's o.k. to trouble shoot with, you can take a risk of damage to the electrical system this way. And very important, this has been brought up in the past. If your 5 amp fuse is blown, replace it with a 5 amp. Or, you'll damage your mpem!.........got $500 bucks for a new one. Me either...
Let us know if you need further assistance.

 

[shawnmstout]

I believe its the mpem

well i found out the guy that had it before put a 10amp in it instead of a 5amp fuse, thanks for the reference material.

Here is what i have done

Replaced the silenoid, no change
Unhooked the regulator because the 5amp fuse is blowing each time. Still blowing the fuse.

So i think its coming down to the mpem, if im wrong or right let me know. I ordered a complete electrical box from ebay last night for 200 so its on its way.

 

[All Things Custom]

10 amp is ok to have been used...

If you want to sell that old MPEM contact me. Or see my thread in the for sale section...

Thanks, Mike

 

[shawnmstout]

just out of curiosity

since this is a common problem, what inside of the mpem is bad? I am a eet and because of this i always want to know exactly what happened to help to prevent it again

 

[All Things Custom]

I can tell you the most common cause is jump starting the ski (usually with a running vehicle) or running a low battery that is constantly drawing too much current from the stator.

Seadoo put a component in their MPEMs from 1993 to present on all 587, 657, 718 and 787 motors that was far too small. They knew about this and their fix was to place a sticker on the inside of the engine bay that stated do not jump the ski while in the craft.

At $300 - $1000 per MPEM I honestly think it was planned obsolescence. They changed their configuration in 951 and 4-tech models and placed glass in the potting compound to keep people from being able to repair the units.

This is based solely on opinion and not fact.

:cheers: