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  1. #1

    787 hesitation at about 4000 rpm

    Hi guys, I recently purchased a 1996 sea doo gtx with the 787 and the twin carbs and also a 1998 787 with the rfi. Both in pretty good shape. I got to take both out today and both run great. I am very happy with them. The only issue that I noticed is that both have bit of a hesitation or a miss at around 4000 rpm, then smooth right out again about 4300 or 4400, and run as smooth as can be right up to WOT. A friend said they all do it, its when the rave valves open, but this a is also a friend that put gasoline in a diesel truck....so..... I thought I might see if anyone else has had something similar. If they were both carbed I would think it was a pop ofd pressure issue, but with one being carbed and one injected and both having the same hesitation, he might be right.


  2. #2
    Clean the raves. 97 had a problem with sticking raves, but that was way more than a hesitation.

  3. #3
    I did check them out, they seemed pretty clean. I will pull them and clean them up, see if that helps at all. Thanks

  4. #4
    I cleaned up the RAVES on the 96 and took it for a quick ride and didn't notice any difference. They were really pretty clean to begin with. I have read a few guys had a hesitation at 5000 where it wouldn't accelerate past that with a load on the engine. This is different. Its like the engines just run rough and bog a bit if you slowly accelerate to 4000 then once they pass about 4300 they take right off and are smooth again. Its odd that they both do it!

  5. #5
    flyin' the friendly skies airbornexp's Avatar
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    Clean the carbs, I bet the filters are partially plugged

  6. #6
    Thats what it feels like to me, but i just rebuilt the carbs on the 96 and the 98 is rfi. Seems weird they both do it at about the same rpm...

  7. #7
    wkuadam07's Avatar
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    Do a search on the rave housings and the factory update on them. Late 96 and early 97 models had that hesitation because the rave housings were bad from the factory. Put some new or SBT rave housings on it and it should get better.

    The RFI will just always do that, i have ridden several of those skis and there is a 4500-5000 hesitation with them. It takes a second or two for the computer to open the rave solenoid and that's the hesitation. It's all because the raves are computer controlled, if the check valve is dirty or faulty on the crankcase pressure line to the rave solenoid it will be worse than normal too.

  8. #8
    Okay great I will order some Rave housings for the 96. Is it worth trying to clean the check valve on the rfi? Is it on the black tube from the crankcase to the Rave valves?

  9. #9
    wkuadam07's Avatar
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    On the RFI there should be a black line from the crankcase to a check valve then the Rave Valve solenoid that is mounted on the side of the hull, from there the black line runs to a tee then to the raves. Make sure the check valve is operating properly and the lines are clear and it may help. If the solenoid is bypassed it's trouble as well.

  10. #10
    flyin' the friendly skies airbornexp's Avatar
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    Quote Originally Posted by metzger66 View Post
    Thats what it feels like to me, but i just rebuilt the carbs on the 96 and the 98 is rfi. Seems weird they both do it at about the same rpm...
    Check your pop off pressure on the carbs. a couple time I have swapped fuel lines, I've got shavings of rubber that fell in the tube get caught in the screens. Did you clean the fuel selector to?

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