thanks TOU... I was thinking along those lines too... I pulled the carb and took it apart. The floats both float in gas and move freely so I figure they must be fine... I'll go and pick up a new needlt and seat assembly tomorrow and see if that solves the problem,
Could also be a bad diapragm in the fuel pump (If the vacuum comes off the mag side on the bottom end) If its cracked it can draw lots of extra fuel into the crankcase, and because each part of the motor is sealed from the other, it will only affect the one cylinder. Worth a check anyways. Good Luck!
Unless the sled is fuel injected, they still use vacuum impulse operated fuel pumps.
And my reasoning behind the fuel pump not being the problem is because he said the gas was coming out the vents in the carburator. So if its coming out the vents, gas in the crankcase would have nothing to do with this problem.
If we did not know that the gas was coming out the vent lines in the carbs, a fuel pump could very likely be the cause for constantly fouling plugs in that instance.
As suspected... Needle and seats...It would shoot fuel out the vent even with out the sled running... Funny thing how the old neelde and seat assembly looks clean as can be and un damaged (viton tip) but won't seat... Oh well!! I took it out for a ride this afternoon and it ran great!
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