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  1. #1
    Olomana's Avatar
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    Exclamation Water pressure problem? slowing down the 300X?

    Hello,

    I'm having an issue with my 300X.
    My RPM will drop gradually from 7500+ to 4000 rpm and start to jerk like it is hitting rev limiter (just like you are in limp mode @ 3000 rpm).
    The difference is, I do not have any alarm going off.

    The problem is very random, it can work well for 10 min - 1 hour at cruise speed or WOT and suddenly you can feel the ski is loosing RPM and will start jerk at a certain RPM point.
    Most of the time, it will settle at 4000 RPM and rev limit you.

    Of course I did the basic stuff,
    Fuel pressure OK
    Injector OK
    Spark OK
    Compression OK
    Belt OK
    Coil OK
    SC 14-15 PSI
    no loose hoses

    ect...

    Ski is 100% stock with 16 hours today.

    It took me almost a month to kind of pin point the problem...

    I have noticed just today that there is barely any water coming out of the engine flushing port while running the ski and it happens only when my RPM are restricted.
    The bypass outlet have water flowing.
    I do know a stream of water is supposed to flow when the ski is running properly.

    Now the funny part... to fix it, I just need to pull out the ski out of the water, plug the garden hose in the engine flushing port. Run the ski for 15 seconds or so, put it back in the water, and voila! It will rev back to 7500RPM +

    What the heck?!

    So my questions are:

    - Is the 300X equipped with a water pressure sensor?
    - Low water pressure = Limited RPM?
    - Does the 300X equipped with a water filter?

    I am a bit confused, why it will work back again just after flushing the engine?
    The ground was checked to see if I have any debris, plastic, seaweed, sand ect... falling from the vane hole, NOTHING.

    Thanks for your help.

    P.S: sorry for the bad resume, and English... but getting irritated with that strange problem.


  2. #2
    nicjak's Avatar
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    sounds like its over heating have you sucked up any sand lately? i would check the water intake off the back of the pump it could be blocked as you say it runs ok on the hose.

  3. #3
    Olomana's Avatar
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    I do stop where it is shallow and ha sand , but problem occur as well when riding in the middle of the ocean.

    Water intake is the one vane guide on the jet pump?

  4. #4
    nicjak's Avatar
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    yes but the sand can set inside the cooling hoses and passages

  5. #5
    Olomana's Avatar
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    Quote Originally Posted by nicjak View Post
    yes but the sand can set inside the cooling hoses and passages
    Ok, I will remove the vane and run the engine on the garden hose and see if anything is falling off.

  6. #6
    nicjak's Avatar
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    it was only a suggestion as the 260x cylinder drain hose to the waterbox had a valve in it and the sand couldnt pass through it thus blocking that hose. the reason i suggested to start at the pump is because thats where the intake water for cooling is picked up, becuse you said it was ok when you reversed flushed it on the hose, another way to check is when reverse flushing on the hose check to see if water is flowing back into the top/side of the pump.

  7. #7
    Olomana's Avatar
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    When you are saying top side, the one on the right of the pump?

    Click image for larger version. 

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    #52014A

    Thanks

  8. #8
    nicjak's Avatar
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    follow the cooling lines 2 for the engine one for the i/c sure you can work it out when you look at it

  9. #9
    Olomana's Avatar
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    I guess I will discover how water cooling work on a PWC work... lol
    Suck it has to be on my first PWC tho...

  10. #10
    nicjak's Avatar
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    follow the hoses into the hull you will see which ones go where, your problem could also be electrical and its just coincedence that it comes good once you get the ski out of the water. does the engine sound like it is running smoothly? if you plug a hose into the flush port and you have a good stream of water out the filter housing on the pump it will be all good. you will need to start and look elswhere. good luck

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