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  1. #1

    99' XLT 1200 isses unresolved

    Looking for some help with my 99' XLT. Riva D-Plate and sensor chips installed (previous owner), wave eater clips, new PV servo motor (PVs cycle when started), oil pump block off installed (mixin' my own), cylinders all running within 130psi (not great but ...), rebuilt the jet pump bearings, Solas prop installed, and local shop installed carb kits (last season, no help). Ski idles decent and will pull a tube BUT will not turn over approx. 5500 rpms except out of water. Seems like it is running with timing retarded a bit or backed out. It has run better but I have been troubleshooting this for about two seasons now.


  2. #2

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    Welcome to the forum

    It is unfortunate that there are many things that can cause the symptoms that your engine has. You will have to go through a process of elimination as a good starting point, and these things are by no means the only things that can cause your problem. It is just that these things are common and should be looked at first.

    Do your valves actually cycle wide open when the throttle is wide open i.e. valve related?

    You are going to have to open your valves manually (you may have to disconnect the cables on a temporaty basis to find this out) and then mark them to show you what wide open is. With the boat at wide open throttle and your seat off, check if they actually open all the way.

    Are your carbs adjusted properly, or better still are you getting all the fuel you need i.e. fuel related?

    Your throttle cable can be adjusted so that the carbs do not open all the way.... almost like you have a govenor on it. Look at your front carb when you are pulling the throttle and you should see your throttle cable attached to the round wheel (which is attached to the shaft inside of the carb.) When you pull the throttle and see the wheel turn, grab the wheel and see if you can make it turn in the same direction even more.

    On the water at idle, do you smell strong gas fumes (as opposed to smoke). At wide open throttle, can you choke your engine or pump it with a primer and it seem to "wake up" or does it fall on its face?


    When the previous owner installed the "D" plate, did they think to check for broken catalytic converter parts in the stinger exhaust or the water box i.e. plugged exhaust system related? Did they put the plate in and it never ran as well as it should, or did this event occur after you got the boat? You will have to remove the water box and stinger, and turn them upside down to check for parts.

    These three things are typically what cause your symptoms, but no one can tell you for sure what your problem is. Anyone else would have to dig in it just like you are going to have to.

  3. #3
    Thanks for the tips Salty!

    The "D" plate install was done well prior to me getting the ski and it did run well for the previous owner with it installed. When I first got the ski it was down due to impeller and wear ring issues but that is fixed. I know that the sensor chip needs to be installed as to simulate an active CAT but I don't get any warnings or "bells and whistles" when I run the ski with the chip sensor out.

    I have run the ski with the seat off and the power valves do cycle but never fully open as that is controlled by the CDI and engine RPMS (I thought). I can't get the ski up to the "magic" RPM number for the CDI to open them fully on its own. I have played with the cable adjustment to allow the valves to start opening sooner. That led to a boggy take off (something I expected) and a slightly better top RPM as the valves started to open but nothing like it should be. I have dropped the reverse gate and nailed the throttle. When I do that, the RPMs pickup to around 6500 and the valves cycle open.

    I'll recheck the throttle cables 'cause I can't remember the last time I did. I do think they're adjusted to fully open the carbs. Never hurts to look again.

    Pulling the choke at WOT does not wake things up and if I pull it fully the engine will stumble.

    Thanks for the advice. Just trying to confirm I am on the right path. I'll post what the final fix is ... when I get there.

  4. #4
    Mighty Mouse's Avatar
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    This is what I would do: Remove the cables from the PV. Manually open the PV all the way and tie it up so it stays open. Take ski out. It'll be doggy on the low end, but around 3600 or so It should pull to 7k or so. That will rule out everything except the PV contol.

  5. #5

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    You may not have the chip, but do you still have the sensor installed?

  6. #6

    sensor chip

    Quote Originally Posted by salty View Post
    You may not have the chip, but do you still have the sensor installed?
    Salty, I have the chip installed in place of the exhaust sensor (as verified at the RIVA Racing site). Also, the orig. exhaust sensor is still in place but the wire lead is just zip tied off to the side. I'm heading out this Saturday to spend some time troubleshooting. One item to note, I'm running a "one step" hotter plug as recommend by the local shop (the guys that installed the carb kits). The plugs look pretty good all things considering and I've compared them to my 98' kawasaki that is running well. Thank you both (Mighty Mouse) for the tips. I'll post if I find it ...

  7. #7

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    Quote Originally Posted by 4dinosski View Post
    Looking for some help with my 99' XLT. Riva D-Plate and sensor chips installed (previous owner), wave eater clips, new PV servo motor (PVs cycle when started), oil pump block off installed (mixin' my own), cylinders all running within 130psi (not great but ...), rebuilt the jet pump bearings, Solas prop installed, and local shop installed carb kits (last season, no help). Ski idles decent and will pull a tube BUT will not turn over approx. 5500 rpms except out of water. Seems like it is running with timing retarded a bit or backed out. It has run better but I have been troubleshooting this for about two seasons now.
    what prop installed (pitch)

  8. #8
    Quote Originally Posted by chip View Post
    what prop installed (pitch)
    Chip,
    I recently installed a Solas Concord 12/18 but ski ran the same with the old stock prop. Just replaced the prop when I replaced the pump bearings and seals a few months ago. Thanks!

  9. #9

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    bud can you take pix of plugs after high speed run.could be running rich or could be crack exhaust manifold

  10. #10
    Quote Originally Posted by chip View Post
    bud can you take pix of plugs after high speed run.could be running rich or could be crack exhaust manifold
    I'm heading out Sunday. Will take pics and post 'em. Thanks.

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