1994 XP runs good, then slows, quits and runs good.

[Bruins]

We have a '94 XP in our shop right now that we just replaced the fuel lines and rebuilt the carbs and replace the selector switch, we have done this to dozens of seadoos with awesome results. But this one runs well for aprox 300 yards and slows to a stall, you start it up, it starts well, and runs good again for another 300 yards. I'd like to rule out fuel issues, because we have the carbs set to factory specs for this model and cause of our experince, but I am willing to hear/read any suggestions. We check the O-ring is in the main fuel filter cup, but i do not know if it is full when it stalls, I assume so since it starts so quickly. We also replaced the pulse line.

Thanks!

[20 feet Boy]

See if the fuel baffle is crack where the fuel lines go into the tank. Also see if the fuel vents are working properly. Sometimes they plug up and might not let fuel flow properly.

[jdonalds]

See if the fuel baffle is crack where the fuel lines go into the tank. Also see if the fuel vents are working properly. Sometimes they plug up and might not let fuel flow properly.

We have the same problem. I'm ignorant about wrenching on SeaDoos. Our 92' XP does just what Bruins does. We have replaced fuel tank components, cleaned the carbs, all fuel lines are black, the pump checks out.

I'm not familiar with the "fuel vents" you are speaking of. Can you offer more of a description to help us out please?

John

[20 feet Boy]

We have the same problem. I'm ignorant about wrenching on SeaDoos. Our 92' XP does just what Bruins does. We have replaced fuel tank components, cleaned the carbs, all fuel lines are black, the pump checks out.

I'm not familiar with the "fuel vents" you are speaking of. Can you offer more of a description to help us out please?

John

The fuel vent off the fuel lines. One is at the top [ should hiss when fueling to the top off the tank]of the ski and the other comes out the side. They sometimes get junk in them making back pressure. I had a bunch of black stuff come out the side one on mine. If the rotary valve cover has groves in it it will all so make the ski run all over the place at idle

[jdonalds]

The fuel vent off the fuel lines. One is at the top [ should hiss when fueling to the top off the tank]of the ski and the other comes out the side. They sometimes get junk in them making back pressure. I had a bunch of black stuff come out the side one on mine. If the rotary valve cover has groves in it it will all so make the ski run all over the place at idle

Thanks for the info.

I tested both one-way vents and they are okay.

We blew compressed air from the carburetor end of the fuel lines back through the reserve/main selector switch in both switch positions. We could hear the bubbles back in the tank so we think it is clear. Still our test ride showed no improvement.

The ski will go for about 1/2 mile at WOT then stall. The longer we let it sit the longer it will run at WOT but never more than 1/2 mile or so. If we restart right away the length of time it will run at WOT decreases.

I played with the choke when it is stalling and can somewhat recover so I'm pretty sure the ski is starved for gas. I don't know what to do next.

If the filters in the carbs are clogged wouldn't it refuse to go WOT (about 42mph)? Since we did a bunch of things to the fuel system and there was no change I'm clueless.

1) Replaced the large rubber component on the fuel tank that the fuel sensor screws into.
2) Replaced the fuel filler cap gasket.
3) Replaced the two siphon tubes in the fuel tank.
4) Cleaned the fuel/water separator.
5) Disassembled, cleaned, and tested (to the best of our limited ability) the fuel pump.
6) Sprayed carburetor cleaner in the intakes while running the ski.
7) Siphoned all of the gas out of the tank and refilled it with fresh 91 octane (did this first before any other actions)
Siphoned all of the oil out of the oil tank and refilled it with West Marine 2-cycle synthetic oil (did this first too)
9) Replaced the plugs.
10) Compression is about 150 in both cylinders.
11) Spark plugs look good after installing new and running for 5 minutes on the water. Both are light brown.
12) The rotary valve looks clean and smooth.
13) We cleaned the small filter in the fuel pump. About 1/4 of it had some residue but it wasn't too bad, the other 3/4 of it was clean.

All of the fuel lines were replaced before we bought the ski. There are no grey lines anywhere.

I'm tempted to replace the fuel selector switch but since it blew out okay it doesn't make sense to me that it would be the problem. We tried switching between reserve and main several times.

The "Main" or "High" needles on the carburetors are both screwed in all the way.

Any suggestions would be appreciated.

Thanks,
John

[20 feet Boy]

I am not familiar with those 92 xp carbs on your ski. The carbs might need to be rebuilt. The pop off press might be off. The low speed screw should be all the way in then back it off 1 1/2 turns. It all most sound like something a electrical is getting hot then shutting down. Then it cool off and runs again. But if the choke thing worked it must be the carbs. airbornexp may known whats up. maybe ask him. He help me before. I sorry I dint help Good luck

[airbornexp]

sounds like you have done everything but replaced the needle and seats. I would replace the needle/seats and the springs and check the pop off. one thing you can do is fire it up, pin it WOT and when it starts to bog kill it and check the plugs. that will tell you everything you need to know. if they are white in color you are burning up a piston, if they are black its too much fuel but that doesnt seem to be the case here. and if they are a chocolate brown they are spot on. check these and do the things above and if thats not it I would lean towards MPEM

[winterstick]

what about the stator coils, not the charge coil, or tried trimmed the wires

[Bruins]

After a Lake Test we replaced the MPEM and have not had the issue again.

Thanks to ALL that helped!!!