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Spitfire SU Carb Jet Assembly Seized

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J

JDub

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Hello SU Carb-heads -
I was just installing new jets on my SU Carbs ('69 triumph spit). Rear went smooth; front - while reinstalling the jet, everything seemed to go smooth until I "screwed the adjusting nut to it's highest position, and then unscrew". I screwed it all the way up - jet bearing, washer, locknut, spring, and adjusting nut seized together, I cannot back the adjuster off at all. I pulled the jet out, took this seized assembly off the carb and tried to wrench the locknut and adjuster nut apart, no joy, greased and wrenched, nothing - I cannot separate these pieces for the life of me. Just ended up ordering a new 'jet bearing assembly.'

Is this heard of? Mechanically I don't even understand how these could 'seize' together, something to do with the compression of the old spring?

I am following the Brooklands Manual for the Spit. Maybe I misunderstood (pg 33) on the jet reassembly. I was just trying to reassemble and with the jet level with the bridge, which seemed to be going fine until I snugged up the adjuster in order to then back off the twelve flats for initial setup.

Any thoughts, advice, criticism welcome!
 
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