Hello all, again.
For a while my carb has been running with the float level too high with the usual results of a black plug and fuel dribbling out of the carb before the engine starts (fine when running).
What is the accepted way of adjusting this level and is this likely to cure the dribble?
Yours in anticipation
Kimble
Some time back there was a discussion of this on these pages. If the float is too high then you'll certainly get a rich mixture. Some things to ask might be: Do you have the right float? And is it coupled up to the correct needle? People often mix and match, with the inevitable results of uneven running. If in doubt Hitchcock's UK have a whole range of Amal spares (and a very good website), and you might want to check with them. They will mail out to anywhere in the world. You should probably buy a float and needle at the same time.
Plastic floats and brass ones do not float at the same level. Some Amal float needles have two grooves in them for this reason, and so can accommodate either type of float.
An M20 should have the shortest nut and the float height is pre-set. But it is possible to alter the height by adding another fiber washer at the banjo. But in reality, if your carb is dripping/flooding? Then it's probably a non seating needle valve. Ron
I had exactly the same problem, but only at low revs. I fiddled with the float height [and changed the needle] for over a year. Eventually I decided the vibration at tickover was allowing fuel to bleed past the needle seat. I bought a new more buoyant plastic float and needle and all my problems went away. Finally adjusting the idle mix made a difference and the bike no longer lurched slightly when changing gear. I stress there was nothing wrong with the old float. It's possible that just a brand new needle may have done the trick but I couldn't be bothered to waste any more time. Er and plastic floats and old floats clip to the needle in entirely different ways. That is the reason new needles come with two slots
