I'm the original owner of a 1998 GTX Limited Dual Carb. I am having an issue that is rather odd to me as I'm rather well versed in mechanics. Just not 2-stroke and skis in general. I have changed the gray fuel lines and the internal carb filters and cleaned the fuel valve long ago and it ran perfect after doing that. Now all of a sudden, this ski started to, what seems to be, drop a cylinder at the low/mid rpm range. It seems to idle fine but if you give it throttle it seems to be running on one cylinder. Then it takes off and anything above 1/2 to 3/4 throttle it runs fine and fast. Drop it down below about 4000 and it seems to surge not holding steady RPM. New plugs had no effect. I would not think it is a fuel starvation issue as it runs fine, and as long as you like, over 4500 to WOT. If you quickly squeeze the throttle from idle it will be on one cylinder, but then take off on two cylinders after a quick moment and is fine. The compression is even on both cylinders. Not sure if this could be spark or electrical issue or if there is another part that could cause this at low/mid throttle? Any help how to diagnose the issue would be very appreciated. I have also just taken out and cleaned both Raves as one was moving freely and one was somewhat stuck. Now both move freely. With new battery fully charged. What I am finding is just about the same. Under slight to half throttle it seems one cylinder is not firing and then adding more throttle it takes off and runs full speed on both cylinders. My thought is that one carb has it's low end/mid-range fuel metering circuit blocked??? I would think it cannot be something mechanically wrong with the engine or it would not run as new at 3/4 throttle and above. Doubt could be the ign. coil either, but maybe?? Looking for any input.
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1998 Seadoo GTX Ltd Low/Mid Throttle issue
- Thread starter p.seadoo
- Start date
Grim
Well-Known Member
Put spark tester on both of them and see if the sparks are the same intensity. If not take the wire out of the boot for the one that is low intensity and cut 1/4 off the wire and reinstall everything, test again. Also, verify you are using the exact spark plug required for the 951 engine.
If the spark intensity is the same on both. Put a meter on the battery, crank it up, note the voltage (should be12V to mid/low 13V), then rev it to 4K RPM or a little higher and note the voltage (high 13 to mid 14v range), if your voltage is low or too high on the high RPM its your voltage reg not performing as requires , if it is within tolerance. I would test the coil.
Also verify your ground at the rear electrical box is clean and tight and the one on the left side front of your engine is clean and tight. Sometimes the groud in the rear box gets jumble with the other two wires at the coil and doesn't produce a good ground.
If the spark intensity is the same on both. Put a meter on the battery, crank it up, note the voltage (should be12V to mid/low 13V), then rev it to 4K RPM or a little higher and note the voltage (high 13 to mid 14v range), if your voltage is low or too high on the high RPM its your voltage reg not performing as requires , if it is within tolerance. I would test the coil.
Also verify your ground at the rear electrical box is clean and tight and the one on the left side front of your engine is clean and tight. Sometimes the groud in the rear box gets jumble with the other two wires at the coil and doesn't produce a good ground.
