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I entirely endorse everything Stan says, although I’m not entirely comfortable with the 1mm fuel height, its right at the maximum I’d have thought. I’d be more comfortable if it was rather lower but then Stan knows the Scott whereas I’ve only a pile of bits although I have spent years doing cruel R&D things to all sorts of machinery. Well that’s my excuse…

The only thing I’d add is to check the weight of the float, it should be 14 grammes, and the float plus needle should weigh 18 grammes. Check the size of the float too, (well you never know!); it should be 40mm diameter x 32mm long. Look for any float repairs, solder is heavy stuff, shake it, see if it rattles; a small increase in weight will make a difference in fuel height although not as big a one as you might think. If there is a sizeable dent in the float make sure it goes to the top on reassembly where the loss of volume will have no effect.

While you are at it I suppose you’d better check the dimension of the float needle too, from the top of the circlip to the tip of the point should be not less than 28mm. If it’s shorter it will have a direct 1:1 effect on the fuel height, a much greater effect than, say, a minor weight increase.

Finally make sure the float bowel is set dead vertical to give what is after all a pretty crude engineering solution the best chance of working, frankly with all the vibrations of a running engine it never ceases to amaze me that the system works as well as it does.