Hey everyone, this is my first tech post and I’ve searched for answers for a few hours now. I don’t think I have figured it out yet so I thought that I would post a question. I will start from the beginning.
I bought a 1995 seadoo xp 720 last week. Brought it home and being a dumbass and get too excited sometimes and overlooked the fact that the flywheel cover was missing 8 out of the required 10 bolts!! And go figure they were all stripped. Not a big deal for me, I am a machinist so I opened the holes up a bit and tapped them ¼-28 fine thread. There was minor surface rust on the flywheel and on the cover/housing itself. I took the time to scotchbrite the shit out of it and clean all the rust off and gave it a light coating of “fluid film rust a corrosion preventer” I then replaced the O-ring(there was silicone in there before). Put the cover on, loctited the bolts and torqued them up. The seadoo was ready for the water... or so I thought!
I put it in the water on Saturday, fired up no problem. Was running great for about 10 minutes. I was taking it easy since this was my first time out with it. Once I started to give it a bit of throttle and start bouncing off the waves it died on me... so I fired it back up continued on. About 30 seconds later it did it again, it did this 3 times on me and then finally it said no more and I had no power at all. The start button did nothing. I got a tow back into the marina. When I looked inside the hull the whole exhaust had come loose. It actually spun one if the top manifold bolts right out. It blew the pipe out of the hose section going into the water box as well. The starter came out of it too!! WTF!!, The screw at the back and the bottom one were in the bottom of the hull. The top screw was in only a couple of threads.
The only thing I can think of is that the guy who had it before me didn’t torque or loctite any of the screws. I thought this was no big deal because I could just bolt everything back up properly and be ready to go back out. Boy was I wrong.
I removed the pipe assembly so I could get at the starter easier. I put the starter back In and bolted it up. I put some oil in the cylinders and wanted to roll the engine over in case water got in there from the loose exhaust. Nothing, no power.... I opened the CDI box and the 5A fuse was blown.. I replaced it and it blew right away. I went through and read all the posts about disconnecting the stator. When I disconnect it, it doesn’t blow, as soon as I plug it in, it blows.
(For the record, the VTS system was disconnected and removed before I bought the seadoo, all of it was unplugged before any of this happened.)
I checked the stator for resistance and I believe the ignition and charging wires are within spec as per the seadoo shop manual. So I am not sure about the stator being the problem. Now.. onto the MPEM...
I removed the MPEM and began to check the resistances as per the shop manual. I’ve never done this before, but basic continuity tests. The biggest reason is that I am not too sure what setting I should be setting the dial to on my digital multi meter. It starts at 200, 2000, 20k, 200k, 2000k, 20M.
Is there a chance by the starter coming loose and bouncing up and down losing its connection with the crank case that it could have arced and fried the MPEM. I think this is why it would run when I was going slow but as soon as it started to bounce on the waves it would die on me. Sorry for the Novel guys, just wanted to explain my whole situation hoping I could find a solution quicker. This is my first seadoo and I really want to get back out on the water lol.
Thanks in advance for any help guys!
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I bought a 1995 seadoo xp 720 last week. Brought it home and being a dumbass and get too excited sometimes and overlooked the fact that the flywheel cover was missing 8 out of the required 10 bolts!! And go figure they were all stripped. Not a big deal for me, I am a machinist so I opened the holes up a bit and tapped them ¼-28 fine thread. There was minor surface rust on the flywheel and on the cover/housing itself. I took the time to scotchbrite the shit out of it and clean all the rust off and gave it a light coating of “fluid film rust a corrosion preventer” I then replaced the O-ring(there was silicone in there before). Put the cover on, loctited the bolts and torqued them up. The seadoo was ready for the water... or so I thought!
I put it in the water on Saturday, fired up no problem. Was running great for about 10 minutes. I was taking it easy since this was my first time out with it. Once I started to give it a bit of throttle and start bouncing off the waves it died on me... so I fired it back up continued on. About 30 seconds later it did it again, it did this 3 times on me and then finally it said no more and I had no power at all. The start button did nothing. I got a tow back into the marina. When I looked inside the hull the whole exhaust had come loose. It actually spun one if the top manifold bolts right out. It blew the pipe out of the hose section going into the water box as well. The starter came out of it too!! WTF!!, The screw at the back and the bottom one were in the bottom of the hull. The top screw was in only a couple of threads.
The only thing I can think of is that the guy who had it before me didn’t torque or loctite any of the screws. I thought this was no big deal because I could just bolt everything back up properly and be ready to go back out. Boy was I wrong.
I removed the pipe assembly so I could get at the starter easier. I put the starter back In and bolted it up. I put some oil in the cylinders and wanted to roll the engine over in case water got in there from the loose exhaust. Nothing, no power.... I opened the CDI box and the 5A fuse was blown.. I replaced it and it blew right away. I went through and read all the posts about disconnecting the stator. When I disconnect it, it doesn’t blow, as soon as I plug it in, it blows.
(For the record, the VTS system was disconnected and removed before I bought the seadoo, all of it was unplugged before any of this happened.)
I checked the stator for resistance and I believe the ignition and charging wires are within spec as per the seadoo shop manual. So I am not sure about the stator being the problem. Now.. onto the MPEM...
I removed the MPEM and began to check the resistances as per the shop manual. I’ve never done this before, but basic continuity tests. The biggest reason is that I am not too sure what setting I should be setting the dial to on my digital multi meter. It starts at 200, 2000, 20k, 200k, 2000k, 20M.
Is there a chance by the starter coming loose and bouncing up and down losing its connection with the crank case that it could have arced and fried the MPEM. I think this is why it would run when I was going slow but as soon as it started to bounce on the waves it would die on me. Sorry for the Novel guys, just wanted to explain my whole situation hoping I could find a solution quicker. This is my first seadoo and I really want to get back out on the water lol.
Thanks in advance for any help guys!
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