2001 XP Limited Winter Project

[1MACGYVER]

I picked this up yesterday, engine is in great condition, hull had a few blemishes but it has an electrical problem:
* Has power, will crank over when the solenoid is bridged
* Power to the computer on the yellow/red stripe wire from the starter box, but i dont measure any voltage at the fuses
* There were 3 blown 5A fuses on the ski...
* I have a spare computer that makes no difference but i dont actually know its condition
* The Dess post has been swapped for a test but made no difference (im told)
* I get no beeps when the lanyard is attatched, nothing when the start button is pressed (apparently even with the wrong lanyard it should still light up the dash or beep)
* I have tested continuity of the start and dess post wires back to the computer plugs and are good

It was missing the hood strut, as it happens the second last one listed in any seadoo dealer in the world was on the shelf at the dealer 5 minutes from my house, happy days

Any ideas??
Thanks
Chris

 

[1MACGYVER]

Anyone got any crazy theories?
Im thinking ive got a bad earth or battery -ve to something.
Or possibly the dess post is bad but so is the beeper so when swapped it didnt seem to change

 

[ocod]

Don't have an idea but ski looks immaculate.
Your super lucky for that hinge. I read its a common problem and $$$
Have you taken compression numbers?

Pm Saber for help he's familiar with the 951 engines.
Maybe he'll have wiring of electronics.

 

[Dr Honda]

Actually... the gauges should come on, just pushing the start/stop button without the lanyard.

To me... it sounds like something shorted, and took out the MPEM.

 

[Dennis]

Your power to the computer comes from a red/purple (not yellow/red) wire that is connected to starter solenoid post with constant 12 volts. I believe the computer ground wire attaches to the front engine cover. :cheers:

 

[LouDoo]

When you tried the spare MPEM does it also blow the 5 amp. fuses?

Lou

 

[1MACGYVER]

Thanks guys, keep it coming

Your power to the computer comes from a red/purple (not yellow/red) wire that is connected to starter solenoid post with constant 12 volts. I believe the computer ground wire attaches to the front engine cover. :cheers:

my error, ive had a bit more of a search through it, it has 12v on the red/purple, if i short power onto the red/yellow it cranks.


i tested it again with another computer again and i do get 12v onto the fuses but nothing anywhere else, it doesnt blow fuses (unless i now have 3 blown mpem's)

i havnt yet run a compression test- i will tomorrow, the pictures are flattering as there is a bit of paint and hull damage that the photos dont show

todayat my local seadoo dealer i photocopied the relevant page of the seadoo bible of electrical wiring diagrams so tomorrow ill keep testing part by part, the only thing i dont know is the logic of the mpem (which sensors, inputs it reads for what values before it lets certain operations happen)

it has been switched to premix and the oil tank is removed, i assume the oil light will just be on as the plug just sits in the hull- could this be a problem?

 

[LouDoo]

Just to humor me, try unplugging the VTS from the electrical system, there should be a two conductor plug just above the battery, with a red and a black wire, unplug it.

Lou

 

[Dennis]

Your description of the situation leads me to believe the computer is not turning on. Don't worry about engine sensors or oil lite at this point because they won't cause the computer to not turn on. Pressing the start/stop button (no key installed) should turn on the computer/gauges. If the stator harness is not plugged in to the front engine cover then the computer will not turn on so check for a good connection there.

 

[1MACGYVER]

so i ran a compression test today, 95-100 psi in each cylinder
also i was testing the mag and it seemed to be open circuit (turns out it only runs a 2 wire coil even though there are 3 wires going to it)
so i pulled the engine out today in anticipation of rebuilding it and because it is easier to work on

it seems the stator harness was fine, i did forget to unplug the vts but ill try that tomorrow.
there must be something that the computer needs a signal from to turn on (like the stator harness)

 

[SabrToothSqrl]

That is correct, if you unplug the stator connector, it will never start. It includes the CRanshaft position sensor so it knows when to fire the plugs.

 

[1MACGYVER]

Thanks
I tested at the computer plug and i get continuity all the way through the stator winding and back to the plug, also i get continuity through that sensor (i assume its the crankshaft pos sensor next to the stator)

i also see 3 wires going into the splitter on the throttle cable, is this a Throttle position sensor? and could that be stop the computer starting?

 

[Dennis]

The throttle cable has a wide open throttle sensor that the computer uses to adjust timing. It won't keep the computer from coming on.

 

[1MACGYVER]

i borrowed a new throttle cable and sensor today and tried swapping it, ive tried with the vts unplugged, ive tested the crank sensor, still no luck

i think the next step is to pull the wiring harness out and test every wire for continuity and or high resistance.

 

[gbone87]

I saw your post that says your oil tank is removed. That is a major concern. You need that for the oil bath for the rotary valve. Without it you will burn your new motor up after its rebuilt.

 

[mikidymac]

True on the 580-787 gbone87 but the 951's do not have a rotary valve so they do not need the oil tank with pre-mix. But good info for us with the "old tech" rotary valves.

 

[Dennis]

Is the engine out of the ski?

 

[1MACGYVER]

Engine is out, i have had the mag housing off the engine sitting in the ski plugged in and all of the earths clamped to it while im testing other things.
Im starting to think i have 3 blown computers

 

[LouDoo]

That's a bummer. Do you know what's blowing the MPEM's? I would check the rectifier and magneto, something ain't right.

Lou

 

[mikidymac]

I think the problem is that darn Ducati. I will take it, please?

Sounds like it would be pretty unlikely to have 3 bad MPEM's as they are fused and the fuses are there to pop before the MPEm does.

 

[1MACGYVER]

That's a bummer. Do you know what's blowing the MPEM's? I would check the rectifier and magneto, something ain't right.

Lou

I dont know if the MPEM's are blown but its starting to look that way, the rectifier on this model is built into the computer

 

[1MACGYVER]

I think the problem is that darn Ducati. I will take it, please?

Sounds like it would be pretty unlikely to have 3 bad MPEM's as they are fused and the fuses are there to pop before the MPEm does.

Its not blowing fuses (though there were 3 blown 5amp fuses with the ski when i bought it), the computers just dont turn on??

 

[SabrToothSqrl]

you removed the engine with the pipe and carbs on it? that's either smooth or what?! lol.

I have a 02 XP and have pulled the engine (sadly) a lot.

I usually remove the carbs #1 (this can be done, and is actually the best way)

then remove the pipe

then remove the engine from hull.

so

1. carbs
2. pipe
3. engine out

but, obviously you can do as you choose.

My engine was now rebuilt by a shop, so I look forward to years of use.

 

[1MACGYVER]

I probably would have but i couldnt really see how the carbs detached, then they were blocking the bolts to the exhaust so i just spit the pipe to make more space and lifted it out with a mate, the exhaust made a nice handle to lift it with =)

Now that its out and i can see it all i will probably strip it down to reinstall it.
I need to find someone with a running ski/computer that i can put any/all of these computers into to test them, or is there anywhere in the world i can send my computer for a bench test??

 

[Guyph_01]

Nice ski, Hope you can fix it. I'm not much of an expert but if you need a hand i'm happy to help