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  1. #1

    Xl800 fuel issues

    Sooo.... Iím not sure whatís going on but hereís what happened and what I notice.

    my wife was coming to dock the ski after a short ride and it stalled out and would not start. I rebuilt the carbs last summer and Iíve had an issue with it running lean. It would bog when I tried to take off and the rpm would never go past 6k. Wave water clips were installed and power valves were cleaned and compression was just above 125psi on both cylinders when I checked yesterday. The power valves cycle on and off after shutting the ski off.

    so I stripped the carbs and couldnít find anything wrong. I tried to do the pop off but thereís conflicting info on here about what it should be whether itís 76 or 40-55. I couldnít check 76 as my pop off tester doesnít even go that high and I couldnít go past 50 as it would bleed past the needle/seat or the pop off tester itself would leak ( crap sbt one I guess) and my poor thumb wouldnít be able to keep up with the rate that it was bleeding by. Seriously why couldnít we have a better way to test.

    So so I put it all back together and tightened the power valve bolts and reed cage bolts and any others Incase it was some sort of air leak causing the lean issue.

    First thing i notice is that my fuel filter is for once full instead of just having a little fuel in it and it holds that fuel in there after I shut off the ski. The ski does now start I must add. But I have not put it back in the water. I did confirm that fuel comes out the return lines.
    Could the ski not have been getting enough fuel due to the pulse lines on the carb having leaks? I previously had the low speed screw out 3 turns and couldnít get it to blacken the plugs. I know have all the screws set where they are supposed to be for starters until I get it in the water and see how it runs. I run premix 40:1 as I have an oil block off kit.

    So so what could have caused it to just die? Hope all this makes sense haha

  2. #2
    Well I have not heard anything from you guys but I did get to take the ski out. Still won’t rev past 5k. I know I said 6k before but I meant 5k. It still wants to bog from 1/4 throttle to 1/2 throttle take off. Sometimes it will take off and plane out without pulling the choke for a split second. Once I’m up it won’t go over 37mph. I have not gps’d It. The plugs are slightly gaining a hint of brown on the porcelain part but still pretty white. The electrode is pretty dark. I’ve gone ahead and ordered a new fuel filter and the 1.5 needle and seat and 92.5 high speed jet. I was using some generic fuel filter and maybe it was not allowing enough fuel. I also got the 115g springs just Incase the ones I have are not right. I’m hoping this will make it all better. I did notice that the pickup lines going into the tank had no zip ties on them and the rubber flange was missing the clamp so I put a new one on. Trying to seal any air leaks.

  3. #3
    Ok so big progress today. Big booboo on my end. Just realized what the accelerator pump was and that it wasn’t connected lol! Way back when I first got the ski and did the oil block off, I thought those lines in the t shape coming out of the accelerator pump were part of the oil injection so I disabled the arm on the pump. I guess that’s why it doesn’t want to get going on take off as it doesn’t have that extra bit of fuel that the pump was meant to serve!

    Question though. Does that pump only serve a purpose on take off? That wouldn’t explain why I can’t get my top end high enough would it? Wow I can’t believe I had it off �� I also found a small hole in one of the pulse lines so I’ll be putting on a new line tomorrow when my parts get in.

    My power valve cycle cycle when the engine shuts off so it’s hard to tell if they are not working. I can’t imagine riding the ski with no seat and trying to turn the power valves to see if my rpms increase. Is there a special way of testing it?


  4. #4
    Under moderate acceleration the accelerator pump is for sure needed. As far as power valves, you can normally kinda hear them/feel movement if you manually turn it.

  5. #5
    Last night I made sure the power valves were connected right. The top cable pulls them open and the bottom pulls them closed. They open and close freely as cycle once when the engine shuts off. They are aligned with the little hole when closed. There are so many threads with this same issue but none of them have been solved. I have read through so many with the exact same issues.

    so last night I got my parts and saw that I had ordered the high speed jet instead of the low speed. So I just used the 90 and 150 jets and installed the 1.5 n/s.

    i replaced the pulse lines as one had a pin hole in it and fuel filter and installed 115g springs. All ports are clean.

    i checked the reeds and they were all sealing and flat. I cleaned up the faces on the silver place that holds the entire cage in place and saw I was missing a bolt there so I found another to fit in there.

    Not sure what else it could be. Surely 130psi would not cause me to get stuck at 5k rpm.

  6. #6
    So, I started it this morning. It took a while to get going but eventually fired up. I then ran out of time and had to leave for work. I did notice that the Valves open while the ski is cranking. This picture shows the hole I use to line it up and set it. The cables are not set in the picture
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  7. #7
    My experience with mine is I went back to a 1.2 seat - the 1.5 were too fat. I also went back to stock springs with a higher pop off. No jetting was needed, since you are premix I think you can get by with the leaner carb settings vs. Oil Injection.

  8. #8
    derick441's Avatar
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    That hole is a alignment for a another hole on the engine. You can put a pin in there and make a alignment adjustment. You really need to get the manual as it is explained in depth

  9. #9
    Quote Originally Posted by derick441 View Post
    That hole is a alignment for a another hole on the engine. You can put a pin in there and make a alignment adjustment. You really need to get the manual as it is explained in depth
    Yes I did mention that I use that hole to set the alignment ��

  10. #10
    I kept trying to start it tonight but it just revs like hell and I need to shut it down. I do see the power valves turn at least once it revs up past 5k. Iím going to add more slack to my throttle cable as I think itís too tight. Iím just not sure what I should start my high/low screw speed adjustments at. Do I turn them out to richen it or in to lean it if itís reving high on startup.

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