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  1. #1

    1999 XPL running 6300 rpms on top end

    Hello to all this is my first post,

    I just picked up a very clean 99 xp with a new motor and recent carb rebuild.
    It runs great, starts great, idles great, but I can only run about 6300 rpms on top end.
    Where should I start? It does have the grey lines. If carbs have to removed do you
    have to remove the exhaust? THanks for any help.

    David


  2. #2

    Join Date
    Aug 2007
    Location
    East of DFW
    Posts
    244
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    21
    NO, fortunately, you can easily take off carbs without removing anything but airbox and shuffling oil tank out of the way. The grey lines are a no-no. Over the years of sitting up, they get full of dried fuel residue that gets flushed through out the whole fuel system. The small particulate matter(brown sludge) will clog up those internal carb filters. When the fuel selector is giving out, it will start leaving grey matter in water strainer.(inline filter)

    When a motor only achieves around the magic 6300 range, first thing I always go for is the raves. Most of the time that will fix the problem. Remove the two screws on each and pull out off cylinder. Make sure they slide easily up and down. If clean and free of sludge or buildup reinstall. Make sure the red or green rubber bellow is installed correctly. Go run the ski. There is usually a slight surge and increase of power around 4800 rpm when these rave valves open up. If you still dont have the rpm increase yet, next remove the black caps off top of rave valves with springs and steel retainer. Put them in storage tray if still out on the water. Go run again. The ski will be noticeably sluggish out of the hole, but should increase top rpm now. If rpm is good now, there are two things to look for next. Either your solenoid/lines connecting or pulse line from crankcase. First things first. Go do a quick test explained above and get back with results. No need to go any further until we know which way to proceed.

  3. +1 by:


  4. #3
    Thanks, I will take it out this weekend and let you know.

  5. #4
    I think I may have found the problem tonight. I found the pressure line
    from the block going to the rave solenoid valve has a hole in it from where
    it was rubbing on the driveshaft. Before that I removed the rave valves
    and everything looked good, no buildup and they moved freely against the
    diaphrams. I will put a barb fitting splice and reconnect two cleanly cut sides
    of that pressure line and try it out this weekend. I have a gut feeling that this is it!

  6. #5

    Join Date
    Aug 2007
    Location
    East of DFW
    Posts
    244
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    Yeha! You `da man. Go hit the water and enjoy!!!!

  7. #6
    Quote Originally Posted by Seadoo timebomb View Post
    Yeha! You `da man. Go hit the water and enjoy!!!!
    Oh Yeah Baby,,, Took out the XPL to my closest lake and WOW! I got top end now!!

    I was hitting 65 on the speedo and about 7000 on rpm. I noticed the Rave opening
    at about 6200-6300rpm is that right or should it be earlier?

    BTW it was a $2 fix!!!!

  8. #7
    Well as was good unitl this weekend. Ran the ski for a couple of hours and after coming out of a really long no wake it started bogging.
    It would take off pretty good then bog after a couple of seconds. It really doesn't want to idle without dying unless I press on the gas.
    It felt like a fuel starvation problem. I still have the grey lines so I removed the carbs to check the small filters inside. They were fine.
    Any suggestions? Do you know how much 6mm and 8mm fuel line I will need? I'm quessing about 10 foot each.

  9. #8

    Join Date
    Aug 2007
    Location
    East of DFW
    Posts
    244
    +1
    21
    You need 12 feet of 5/16 and 8 ft of 1/4 from your local auto parts store that carries Gates rubber fuel line. Make sure you remove the fuel selector completely OFF ski. Thoroughly inspect and clean out well. It should click on each position and not really tight feeling when turning. Check in ON and RES positions , blow in air making sure it doesnt leak on closed side or anywhere else. If any issues at all, replace without question. This is the highest part of fuel system and the most common place residue and buildup occurs. When tightening down small stainless hose clamps...screw down only tight enough so hose does not easily rotate on barb fitting. Especially important on any of the plastic barbs.

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