WFO Speedracer
A lifetime ban is like a lifetime warranty !
- Location
- Alabama
No DESS on 94 models
Only models with the Multifunction gauge drain batteries
Yes then you could build engines instead of chasing down electrical gremlins.
Other helping a guy i work with 94 seadoo xp
- Thread starter chips
- Start date
WFO Speedracer
A lifetime ban is like a lifetime warranty !
- Location
- Alabama
Not really the only thing ignition related in the MPEM is the rev limiter which is tied to the stop circuit, you can disconnect the wire from the MPEM to the coil on the 94-95 models and bypass the rev limiter for testing, you will have no stop circuit, that particular MPEM is fried more than likely the diode in the circuit is blown which causes the 5 amp fuse to blow. No one can know how many time that thing has been jumped off with battery chargers , other skis or jump boxes, an absolute no- no on a Seadoo. Once you let the magic smoke out it is never the same again !
lol another update. well i think this thing is the culprit. saw some smoke come out of it and was super hot. Would this thing being bad cause it to gradually run worse and worse and now not at all and maybe the issue was never with the fuel system...??
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alright still dont have this figured out. today i started testing the mpem. I replaced the 5 amp fuse and it blew right away, so i started unplugging stuff until it quit blowing the fuse. after some testing the culprit was the red wire that when i traced it goes to the speedo.
So i unplugged the connector up front that the wire goes to and the ski finally started!! But it didnt run good and didnt want to idle. So what im wondering is what exactly does the MPEM box do, and since smoke came out of it im assuming its bad but will that cause it to run poorly? i figured if it was bad it wouldnt start at all but it does. Also while i was in the ebox i noticed a white wire that is cut right where it goes into the ebox. you can see it at the top of the picture. Cant see where that wire would of went? Any help is appreciated. Just want to make sure that mpem is bad before i tell him to order one. Thanks
So i unplugged the connector up front that the wire goes to and the ski finally started!! But it didnt run good and didnt want to idle. So what im wondering is what exactly does the MPEM box do, and since smoke came out of it im assuming its bad but will that cause it to run poorly? i figured if it was bad it wouldnt start at all but it does. Also while i was in the ebox i noticed a white wire that is cut right where it goes into the ebox. you can see it at the top of the picture. Cant see where that wire would of went? Any help is appreciated. Just want to make sure that mpem is bad before i tell him to order one. Thanks
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WFO Speedracer
A lifetime ban is like a lifetime warranty !
- Location
- Alabama
White wire goes nowhere, the 93-94 XP motors had five wire dual coil stators, much better spark, much stronger output, in 94 they used leftover looms from the five wire stator on the 94 GTX models and used the cheaper single coil stators and just cut the white wire, you can stop looking now, it goes nowhere.
Like I said disconnect everything on the MPEM but the red wire that goes to the positive battery post on the solenoid and the black ground wire that grounds at the coil and the ground post inside the elect box, if it blows the 5amp fuse then the MPEM is dead due to a bad internal diode, If it doesn't blow the 5 amp fuse then you have something shorted to ground, the red/purple wire is system power for the gauges and anything else wired in, black is system ground.
Anything from a speedo sender wire pinched under the jet pump to a gauge shorted out can blow the 5 amp fuse.
BTW Yamaha guys this is what the inside of an electrical box should look like , not like the inside of Davey Jones locker lol.
Like I said disconnect everything on the MPEM but the red wire that goes to the positive battery post on the solenoid and the black ground wire that grounds at the coil and the ground post inside the elect box, if it blows the 5amp fuse then the MPEM is dead due to a bad internal diode, If it doesn't blow the 5 amp fuse then you have something shorted to ground, the red/purple wire is system power for the gauges and anything else wired in, black is system ground.
Anything from a speedo sender wire pinched under the jet pump to a gauge shorted out can blow the 5 amp fuse.
BTW Yamaha guys this is what the inside of an electrical box should look like , not like the inside of Davey Jones locker lol.
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alright replaced mpem and put it all back together. Fired up and ran for a couple seconds then i shut if it off. I am going to take it to the lake tomorrow and see what happens. I still don't thing it is running/idling how it is supposed to. seemed real laggy on the throttle when i had it runnin for a second.
WFO Speedracer
A lifetime ban is like a lifetime warranty !
- Location
- Alabama
Laggy usually means its too lean, come out on the low speed screws till the lag-bog goes away, if adjusted correctly you should have to idle it back up with the idle screw to get it to idle, if you adjust it for best idle quality it will be way too lean and will not pull off the bottom
WFO Speedracer
A lifetime ban is like a lifetime warranty !
- Location
- Alabama
They are adjustment screws, if the carbs did not need adjustment they wouldn't have adjustment screws, I reckon.
Speleopower
got a Superjet
- Location
- Cocoa Beach
Do you have a primer on your Sea Doo? My '94 SP has a lag issue as well. Like WFO mentioned it is usually a lean condition just off of idle. My SP will idle all day long but as soon as you give it some throttle it dies. Unless I give it a shot with the primer pump. Then it will take right off and run at 1/2-full throttle all day long.
I've started to play with the pop off pressure and jetting to get it so it won't lean out when I give it some gas.
-Scott
I've started to play with the pop off pressure and jetting to get it so it won't lean out when I give it some gas.
-Scott
WFO Speedracer
A lifetime ban is like a lifetime warranty !
- Location
- Alabama
Go back to square one and figure out what you don't have , spark, compression or fuel, make sure the rotary valve is rotating also, one more thing these chokes are not like Yamaha chokes, they actually work, make sure you didn't flood it out trying to start it.
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alright messed with it more tonight and still nothing. Has good compression, Has spark. Has fuel. Still wont start. I pulled the ebox back out and checked all my connections, everything's good there. pulled the plugs a few times to clear the fuel if i had flooded it and still no start. i cant imagine i did something wrong while rebuilding the carbs because even if i put gas right down the carbs it wont fire, and i can tell its getting gas. How can i tell if the rotary valve is spinning and what does that do? is it possible that im not getting enough spark for some reason?
WFO Speedracer
A lifetime ban is like a lifetime warranty !
- Location
- Alabama
Yep pull the rotary valve cover and make sure the brass gear on the rotary valve shaft hasn't sheared, when you get the rotarty valve cover off put a zip tie around the gear part sticking out so the rotary valve stays on the shaft, hit the start button, does the rotary valve move when you do this, if not you are fawked.
WFO Speedracer
A lifetime ban is like a lifetime warranty !
- Location
- Alabama
One more thing sometime when you pull the rotary valve cover the rotary valve sticks to it, make sure that does not happen or you will have to retime the rotary valve, of course if the brass gear is toast none of this will really matter
Yami-Rider
TigerCraft FV-PRO
- Location
- Texoma
Rotary valve cover is right under to carb., so yes you have to remove carb. air box etc. to get to it.