Dead 95 GTX. Help.

[Pendragon]

Dead 95 GTX. Help. Dr. Honda come in please.

Hi, how are you doing. Ok so here is the deal. I took my sea doo out to the lake yesterday, and the ski ran great for most of the day. It ran the best it has sense I owned it. It was a great time. My wife and I took it out for another run (we were trying to kill all the fuel for winter) and out in the middle of the lake it just died. Once it died, it would not restart. We let sit for awhile as we drifted farther out into the lake, tried to restart but it would not restart. After the lifeguards towed us in and I pulled it out of the water. I could not get it to start even with starting fluid.

Flash to today, I charged the battery and tried to start it. I started but runs really bad. At idle it has a loop. Almost sounds like a car with a big cam in it. As i rev the motor up it sounds like its hitting a rev limiter but it will do that at all ranges of the rpm band.

I pulled the carbs and checked the little filters. They had some paint chips in them from the hose fittings. I pulled the fuel filter bowl and filter out and that was fine. After I checked that i started it and it was still doing the same thing.

Next I pulled the head off to make sure there was nothing wrong with the slugs and they are both in good shape. Checked the bucket walls and they are fine. I put the head back on and checked compression and and i am at 130 on each slug. It does look like i might be rich on the fuel do to the whole slug is covered in carbon. and the plugs where good and black, but i don't think that it would run great for half a tank of fuel then just stop dead and not restart.

Oh and i don't have grey lines anymore.

Any help would be appreciated.

 

[Minnetonka4me]

slugs and bucket walls...lol those are some new terms!!

Boy with the things you have done this one is a tuffy. Total long shot is the key on the flywheel broke loose and it got off time, maybe the rotary gear jumped a tooth. I had a 97 SPX that liked to do that every once and a while.

Keep trying stuff and report back...

 

[Pendragon]

Yeah the next step was to check the rotary valve but I wanted some other ideas that might be it before I go that route. I don't know if its the key on the flywheel. I just had that happen on my X2 a few weeks ago, and when that went there was not start for it at all.

Keep bouncing ideas my way. Could the plugs be fouled out so bad that it wont run good?

 

[Pendragon]

Ok so i have checked the Rotary valve and it is in place and good standings with life, and still have the surging idle. So its still a no go on smooth idle.

 

[Minnetonka4me]

Check the rectifier...and yes I've had some bad plugs throw me for a loop....

 

[Pendragon]

Ok so i finally got a chance to check voltage at the battery with the ski running. With the ski off i have 12.5v. with the ski at idle I get 12.48 and when I rev the motor up i get 12.51. Does that mean that my rectifier is bad, or is it the charging coil?

 

[Dr Honda]

Yep... The regulator could be bad, and passing AC. (the electronics don't like that) But, check the coils to make sure the don't show continuity to ground.

 

[Pendragon]

Ok, so I just finished swapping out the regulator with a new one and it did not change anything with the ski. I also changed the coil with another one and that i had not change with either. I dont have continuity to ground with the coils. What I did notice is that another owner put in a Rev limit module that you can raise the revs on the ski and he had it raised by 1600 rpm. So any ideas on what could be then next step to try. I have removed the module already and tested with no effect. is there anyway that module messed up anything in the electronics?

 

[Dr Honda]

Yes... the aftermarket rev-limiter could have damaged the MPEM... but it's a very small chance.

If it still sounds like it's stuttering... and you have a new stator, and regulator... I would be looking at the coil and ignition wires next. If they are leaking voltage... it will have a miss. It is common for the wires to break down internally. It is also common to pull the boots, cut the ends of the wires, and put the boots back on. (That is the most common failure point)

I went back and read your original post. A piston that is fully covered in carbon is a sign of running lean... not rich. In a 2-stroke, when a cool, rich mixture enters the combustion chamber... it will actually clean the carbon off the piston crown. The ideal fuel mix will leave the piston crown in about 90% carbon... but you will have about 15mm of clean coming from each of the bypass ports.

Knowing that... I would also be looking for an air leak.