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  1. #1

    Join Date
    Nov 2006
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    99 XL760 wont start? LOST.....

    A SBT engine was just installed and carbs rebuilt. It was hard starting the very first time but once i got it going it was fine for the rest of the day. Also running premix 40:1. The first tank i ran no more then half throttle and in a day got it down to about a 1/4 tank. Added fuel and oil and the next weekend went to go back out and havent been able to start again. I checked compression and it is 150 in both, charged the battery, changed the plugs, and even poured a little fuel down the spark plug holes and it didnt even back fire or try to fire over. I removed the carbs and found that one diapharm to be causing that carb to pop before 35psi so i replaced the diapharm and both carbs poped at 35psi. Replaced the carbs and after a while (pouring fuel in both the carbs) i did get the ski to start, let it run for a few seconds and shut off then tried to restart and it wouldnt. walked away and came back and it started right up, shut it off and it started right up again. walked away and came back and it wouldnt start again. i called it a night and the next day tried to start and it wont, i remooved the fuel pickup to make sure there was no blockage and there is not and i blow through the line so i know the fuel cock is not completely blocked but i did order a new one since it is so hard to turn. Any ideas???


  2. #2

    Join Date
    Nov 2006
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    i have tried pouring fuel in the spark plug holes and nothing, just cranking, the gauge does not even come on (i did make sure it was not in lock mode).

  3. #3
    The gauge doesn't seem to come on until it actually starts! ! when it's not starting you need to verify whether your getting spark? and a diaphragm doesn't dictate pop off that is a needle, seat and springs job! as a matter of fact when u verify pop off the diaphragm isn't even on the carb! I can give you some links to do your cabs properly if u like? Z

  4. #4

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    i pulled the plugs and left the caps on and held to the top of the heads and cranked and it sparked (both). As far as the carbs go you are correct about the n/s and spring and i do test with no diaphragm in place but i also retest once fully assembled and in this case the diaphragm was hitting the spring arm which in turn was causing the needle to lift and air to get through and it was popping at all different psi's. i was able to simply open the carb up with out having to remove from the ski since i tested fully assemblied (before install) and i replaced the diaphragm and bingo 35psi pop.

  5. #5
    interesting! was the diaphragm hard? well at least you dissolved my concern that you did the carbs wrong! you can bypass the fuel system by pulling the fuel line near the filter and sticking it in a small container of premix!
    at least you'll see if the pump is working but sure sounds fuel related?

  6. #6

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    i agree that it sounds fuel related and i plan on taking the carbs off again but shouldnt i get some type of ignition when i pour gas into the cargs and into the spark plug holes? i would think it would at least kick over with the fuel i directly pour in, no?

  7. #7
    krispaintballz's Avatar
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    Sep 2007
    Location
    Kenosha, WI
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    Quote Originally Posted by smitch022002 View Post
    i agree that it sounds fuel related and i plan on taking the carbs off again but shouldnt i get some type of ignition when i pour gas into the cargs and into the spark plug holes? i would think it would at least kick over with the fuel i directly pour in, no?

    On my gp1200 same as yours just add a cylinder i think, when i poured gas in my carbs it would start right up. I couldnt remember if you tried that? I am guessing no primer unit. You are running the choke right? I bet its some type of fuel prob. But when i start my gp1200 1998 even if it doesnt start my display will light up and tell me my fuel and oil.

  8. #8
    It should at least fire unless you get the plugs wet? but if you have spark ? I don't know why it wouldn't at least burp

  9. #9

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    ?????? i cant figure it out myself

  10. #10
    How did it run when you got it going before? how are the reeds? and your sure it's a decent battery? if it were me and I was confident of all else I would go to carbs again! did u use OEM mikuni parts? did you do the fuel pump side also?

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