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  1. #1

    Diagnose my carb tuning symtoms......

    I just rebuilt and cleaned my carbs and I am in the process of tuning the low speed screws. I did a high speed run and the RPM's and plugs look good so I am focusing on the low speeds right now.

    The ski has a little trouble starting. I have the press the throttle just a little bit to get it going but after that it idles good at about 1250 RPM. With the ski warmed up and idling for a little while I go to punch the throttle and It bogs down, sometimes it will shut off and other times with will bog for a second and take off. If I feather it a bit it takes off pretty good.
    When I am up to speed at WOT and let off the gas it takes a little while to work its way down to idle speed, but once it is around 1250 RPM I can mash the throttle and it takes off perfectly. It only bogs if I idle for a minute and then try to punch the throttle.

    My hunch is that the low speed adjusters are too rich right now since they are at about 1 turn out and stock is 5/8. If I lean it out any more it bogs every time I punch the throttle, even after a WOT run. Any ideas? Pop off pressure was at 20 PSI for all 3 carbs.

  2. #2
    thester71's Avatar
    Join Date
    Jun 2009
    central ma.
    Did you remove the thermostat? I've been told that removing the t stat can cause a hesitation after idling for a while.

  3. #3
    Wow that was a fast reply. No, I didn't remove the thermostat. But that would make sense. I wonder if my idle is so rich that it cools down too much after idling for a little while.

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