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  1. #1

    Another powervalve problem.. GP800R

    hey guys. Ive been lurking here for awhile, but now I have an issue I would like your opinions on so I finally registered!

    03 GP800R, the powervalves will not actuate while the boat is in the water. take it out of the water, rev it up, the valves actuate. go figure.

    When on the lake, it seems like the servo tries to turn the valves but they don't move. With the powervalve cables disconnected the valves, by hand, turn pretty darn easy and smooth. I have already replaced the servo motor with no good result (anyone want a servo motor for cheap? lol) .

    I'm no mechanic so I need some help. I really don't want to tear this thing down any further than I have to. Summer is flying by and I want this thing back in the water! I appreciate any advice!

  2. #2
    Moderator OsideBill's Avatar
    Join Date
    Mar 2006
    United States
    Welcome Flay, You have rode this with the seat off, and they do not move at all? Have you at least pulled the covers off of them to inspect? not that hard of a job, 4 bolts on each and gaskets can be reused. Do you have wave eater clips on them? might be you have a dropped valve the servo will move but the valve does not.

  3. #3
    Waveruiner pauladave's Avatar
    Join Date
    Mar 2007
    Clayton le Woods, North West England,UK.
    No idea why they work on trailer but not on water! If the motor 'tries' to open the valves on the lake, are you sure the cables aren't too tight? Also, the valves only open from 5000rpm. Is the ski not pulling enough revs on the water to actuate the valves, but revving free on the trailer it is? Just a thought. Cheers, Dave.

  4. #4
    Rode with the seat off with a hand on the cam that the servo cables connect to engine-side, and they weren't moving. Secured on the lift with the jet in the water I thought I saw it start to turn once. It hits 6k on the tach. Brought the lift up, jet out of the water and the valves actuated every time.

    I tried to remove the powervalve covers, but the exhaust is in the way for the bolts to come out. Thats my next step though, to remove the exhaust and check out those valves. I'm not sure what wave eater clips are, so I assume I don't have them on. This boat had a powervalve break off and fall into the cylinder, but we just replaced everything with stock parts and didn't even touch the other powervalve as there was only about 50hrs on the clock.

    pauladave, you have me thinking. Even though the tach reads 6000rpm, maybe it's just horribly innaccurate (like the speedo) and the motor really isn't getting up to speed?. Could this be the case? If that does make sense, I wonder where I'm losing power.
    thanks for the help!

  5. #5
    Bump for any more pointers.
    I havent retrieved it from the lake house yet to work on it, any ideas/guidance tremendously appreciated!

    pauladave, I just noticed your avatar pic with the Rossi themed waverunner.. it looks sweet! My yami R6 is my main money pit. take it to the track as often as my bank account will allow!

  6. #6
    Verdict... Both PV's broken well.. 1 of them the pin came out and dropped down, the other broke the valve off the stem. I can't believe that this boat has ~80hrs on it and this crap keeps happening. The first time, one of the valves broke and dropped into the cylinder (~65hrs) , ultimatly siezing the motor and busting up the piston. Ridiculous. Ordered a pair of R&D billet power valve kits so, fingers crossed, it won't happen again any time soon!

    Edit: are these failures this common, or do I just have bad luck? the valve that didn't break was starting to fracture at the same spot the other two broke

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