2000 Seadoo Rx problem

[Doug212]

Ok, I recently purchased 2 Seadoos. My 98 Gtx Limited is doing great. My 2000 RX is not so great. I started having a fuel problem and the RX was shutting down at WOT. So I replaced the grey fuel lines and cleaned the internal filters in the carbs. The RX ran perfect yesterday and I was hitting about 62 mph. Then today, my RX ran like brand new, I looked down and was doing 70+ mph not long after that i lost power and almost all compression in both cylinders. I took the exhaust off and removed the head and found the cylinders were etched and it looked like the rings were welded to the pistons on one side of the pistons. I don't know what caused this condition and I'm at a crossroad.
Should I buy a new 2 stroke 951 cylinder and top end kit or should I have the cylinders rehoned and put in a top end kit.
I have aftermarket intakes on the carbs and I read a post about water getting into the carbs when ski is running causing problems for the pistons and rings.
Any input would be appreciated!

 

[Dr Honda]

The melted pistons are from running lean. The damage was probably caused when the filters were plugging up, and the final blow was when it was run hard.

I would send the jugs out to be cut, and buy a top-end kit. While the jugs are out getting machined... rebuild the carbs.

Once back together... it should be fine.

 

[Doug212]

Wiseco Part#: 716M08940
Displacement: 982cc
Bore - Standard: 88.00mm
Bore - Actual: 89.40mm
Bore - Oversize: 1.40
Stroke: 78.2mm
Cylinders: 2
Note: Cylinder boring required
These are the pistons that are in my 2000 RX Seadoo. Does this mean that the cylinders have already been over-bored? Can the bore go larger? There is scratches and etching in the cylinder walls but nothing deep. You can feel the etching more than you can see it. SBT has a 2 stroke cylinder exchange program. I'm weighing my options here.

 

[Dr Honda]

If those are in your engine... yes, it's been cut.

The SBT exchange is a good/easy top end kit.

 

[Doug212]

Ok, cylinders and pistons coming next week with a top end gasket set. I purchased an oil pump block off plate and Im going pre-mix. Anyone have any last minute words of wisdom before I reassemble everything? While I'm waiting I will rebuild the carbs.
Fuel lines and petcock valve have been replaced. I am going to do a fuel baffle repair on the f1 fuse, do i need to patch the baffle?

 

[Doug212]

Thank You Dr Honda

I have looked through a lot of posts and I see where you take the time to reply. I see a lot of good advice to a lot of people. If everything goes well with my RX, I will be back on the water by next weekend!

 

[ski-d00]

No, you don't need to patch the baffle, just drill a 1" hole that is centered 1 1/4" down from the bottom of the ledge. a hole saw with a short pilot bit works well but careful not to drill into the pc board.

 

[Doug212]

I went a little to deep on the fuel baffle and took out 1 of the cross pieces that go all the way down to the bottom of the baffle. Can I remove the cut up piece or can I solder a bridge in its place? I'm sure the piece I cut was a sensor for the magnet on the magnetic fuel float. Its the 1st cross piece below the f1 fuse.
Hopefully I didnt trash the fuel baffle's chance of working.:ack:

 

[ski-d00]

not exactly sure what you are referring to but if it is the top magnetic reactive resistor then you can't just solder over it or your tank will always read full. you can leave it open but your tank is going to read empty when it is completely full but will start working again when the fuel level goes down a little bit.

you can test what the fuel gauge will read by measuring the resistance after the F1 fuse fix, just put the float back in it and tilt it back and forth with a multimeter attached to measure ohms. 90 ohms = full tank, 0 ohms = empty tank

 

[Doug212]

Thanks ski-d00, fuel baffle is working again. Lets face it, gas tanks don't stay full for long. When the tank is full the fuel gage doesnt register, I can live with that.
Well, I have my new top end kit and re-sleeved cylinders and tomorrow is the day. Any last words of wisdom?

 

[Doug212]

951 motor went back in today and I rode it for the break-in period. Runs great! I sure am glad I took your advice about rebuilding carbs!
Now here is a tricky situation. How do I get to the nut on the bottom of the exhaust pipe to tighten it? The carbs are right below and a standard open end wont fit on it. I have a small leak there and I would really like to tighten that nut!

 

[ski-d00]

Unbolt the carbs,let them hang. Plenty of room to torque properly. A leak there can ruin your engine quickly.