HX dies in water, and XP wont rev at all

[mykboo]

Greetings from the Philippines.

I recently had my Seadoo HX 1997 rebuilt with a 720 cc engine and an APE exhaust. It runs great on the trailer except for some backfiring issues. We put it in the water and it wont start. We tried starting it on the trailer then launched it with a rider on and had the engine revved up but it just dies once in the water. Ive tried to research and it seems the engine is running too lean causing the backfiring. but id like to know if this case is limited to the carb or other issues are involved as well. Please do give me your inputs.

Also I have a 1997 XP2 running the 800cc engine and a Factory pipe. Runs great on the traielr as well but in the water it only idles. No matter how much I pump the throttle it hesitates to accelerate and just seems to bog down. Releasing the throttle actually gets the revs back to idle and that is even higher rpm than with the throttle on. WOT just makes the XP die. I need your help guys! Thanks in advance!

 

[Dr Honda]

Check the compression on both skis.

On the HX... re build the carbs, and check the rotary valve timing.

On the XP, if the compression is good... rebuild the carbs.

 

[mykboo]

thanks Dr. Honda. With regard to rotary valve timing do you know the specs we should follow? Im sorry not a mechanic but it would help us greatly if you have an idea what specs we should follow!

 

[Dr Honda]

If you are going to check the rotary valve... you will need the shop manual. It's not easy to explain.