SU H3 Jets Initial Setting

Is there anything in any SU carb manuals as far as a recommendation for an initial setting of the jets, prior to adjusting them while the engine is running?
Perhaps something like “run the screws up all the way, then back off a number of turns”.
I imagine if they were too high it might be hard to get the engine to start.

I would usually put the jet tube equal in height to the outer sleeve, that you can see in the bridge and I would back it down till it was about 0.040" to 0.050" down from there.

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Hi Rob, I have not found a recommendation in the S.U. Workshop Manual Carburetters and Electric Fuel Pumps AUC.9600 for initial setting of the jets.

If I remember correctly, (which I oft don’t) for a car I had years ago, the initial setting was to wind the jet up to be flush with the bridge then wind back one and a half turns. It worked well.

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Think the burlen website has the manuals for setup and tuning available but think the 1&1/2 turns out and try is the starting point

Well, I measure the thread of the adjuster screw as 1/4-26 BSF.
So one turn is .038" and 1.5 turns is .058"; so you guys are all right! :saluting_face: