After Market Mpem's Info.

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I read many forum's but once people fix their issues they don't follow up on it worked out or any details on any other issues they worked out.
So I am sharing my experience .
My issue when I bought a used 1996 sea-doo GTI 717 5865 . I own a lakehouse so I have a advantage of trial and error in the water.
So as I dropped it in the water and drove it to the dock It ran a little rougher as Minutes went on then died 10ft from dock. No start , dead..
Details of what I knew; Battery is new , after market Mpem ( you cannot order new ones , they are factory discontinued , original owner Jumped started it and blew original Mpem , oil injection changed to Mixed gas and was told it had a poor fuse connection which he fixed on Mpem . also said he rebuilt Carbs.
Ok , 3 weeks later of messing with trial and error these are my findings .
1. Unplugging 5 amp fuse would reset mpem and then starter would work .(only for 4x's leaving from dock)
Ah I thought I thought maybe need a little cleaning on contact .... Nope !
2. I could not get past 1/2 throttle , would rev then drop and go back to idle WTF ( Rectifier?) Nope , Carb settings? In - out screws ,adjust...Nope!
............after adjusting carbs many times it died again (only for 4x's leaving from dock) and No start ....
Things I discovered as I pulled it from lake and into garage.
Pulled carbs apart found large washer on low needle valve assembly which kept needle 4 turns out on 1 carb, also high speed retainer knob missing and set 1 turn out , suppose to be zero to 1/4 max out.
My carb problem of 1/2 throttle was caused by a missing oring in the front fuel assembly which cause air to be sucked into the fuel line under load or heavy long throttle . Oring can easily fall out when you clean filter and unless you see it you will never know it.
Then issue 2 was the Mpem would reset after battery disconnect and start ,maybe 2 trys then dead, disconnect and resets.
Hmmm, pulled out ohm meter Mpem Black/yellow strip works with black ground from safty switch post. After market Mpem does not use White , but white is center pin on post, so I connected white along with black/yellow at mpem and put foil in lanyard connection and it worked .
**********My issue was the magnetic safety post ( which I also replaced after 1st week) with a new one was losing contact by the Lanyard line .Sometimes it worked and sometimes fail. Remember After market MPEM's DO NOT REQUIRE programming (these are security Bypassed and can be stolen easily).
***** So i went out and bought a Valmar Marine Universal Kill Switch for 18$
spliced into post switch and combined white with black/ yellow to 1 terminal then black to other , switch has both options to connect or disconnect when pulled .
Also noted that I found a bad pin assembly that connect the on/off push switch , someone pushed it together on angle and force female pin out back of plug. That also cause no start contact issues at times.
++++++++++ today I am gonna sync the carbs , then adjust tune low idle screws 1/8 turn at a time to get it to purr. 8-8-20
I will follow up in a few weeks to update any more issues I come across.


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Also I forgot to mention was the.... little rougher as Minutes went .... was because the link carb screw jam nuts were lose and unwound as it idled .
8-28-2020 update .
What a learning curve.....
1st Remeber that I mention the loss of power on open throttle , well it also turns out that the carb pressure valve on the back carb was bad with a leaky oring.
Note **** when you rebuild these carbs you must use a pressure pump gage to test them ,23$ item. My carb did not hold the required min psi. This caused fuel to pour into motor then spray . Also it keeps fuel from going through the High speed valve at low rpms which causes a toxic rich condition.
The springs in the mikuni carb must match on release . I have found some great free information on these carbs and have the pdfs, also here is a link you can download free 1996 seadoo manuals .

www . mediafire. com /file/7638byavkd6tcnh/

You must connect the www and com , remove spaces
I circled the correct one to click on , these sites always try to trick you


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