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Setting float level

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Nelson

Nelson

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When adjusting the fuel bowl float level should it be adjusted with the lever held down,that is with the needle valve closed, or should it be just resting on the needle by its own weight?
 
Neither, it should be checked with an 1/8 inch drill bit. See the pic in the manual. kind of hard to explain but easy to do.
 
The instruction sheet that came from SU with the rebuild kit for my carbs shows the inverted float chamber lid with a 7/16" round bar used to gauge the forked lever space above the lip. My carbs are H4's. No mention is made about whether the lever should be pressed toward the lid or left alone. I have some material that was sent to me a while back about setting up SU's that stated the float needles should be closed when adjusting the levers. This was in a reprint from a Jaguar manual. This is where I am confused. I'm guessing that I should not be pressing on the levers when I do the measuring but I'm just not certain.
 
I think the goal is that the float pushes the needle closed just as it reaches that 1/8" clearance so I did mine by that method. I went so far as to blow gently into the fuel line and raise the float slowly with my finger until the air quit, then I checked that it was at 1/8". My first time ever messing with SUs so take it for what it's worth. I have Grose Jets too, not that it matters.
 
H4's are 7/16"

Hold th' lid so th' float dangles from above at 90* to horizon to set it.

Then use th' "Blow method" to make sure th' needles shut off th' flow.
 
With the no load gap at 7/16, the gap is about 1/4" with the needle closed. I have the needles as supplied in the SU rebuild kit.
 
Should be good t' go!
 
Thanks for all the responses. When I took the car apart in '73 I didn't anticipate that it would be until this year before it was back on the road. The body is now ready for paint and the engine is back in and almost functional. Hopefully this fall this project will be able to be terminated. :yesnod:
 
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