[AT] Zenith Stuck Jet Removal

[Ben Wagner]

Hello,

I am in the process of rebuilding a Zenith carburetor on a Gravely L; I 
know this is a tractor group, but we do have Zeniths on tractors!  This 
Zenith is nearly identical to the ones on my Farmall A's.  Someone along 
the way attempted (vainly) to remove the brass

~main jet
~main jet passage plug
~well vent jet
~idle jet

and did a terrible job of using a screwdriver.  The notches are 
stripped!  Furthermore, whoever installed them either torqued the jets 
or applied a sealant.  I had enough left to get my screwdriver in place, 
but even after days of soaking in penetrating fluid, the parts will 
still not budge.  My screwdriver doesn't have enough power, even clamped 
in a vise with all my weight on the turn.  I don't want to damage the 
aluminum bowl, or the threads, so I need a way to extract these stubborn 
parts.

I was able to remove the needle seat with my screw extractors since the 
notches were stripped on it also.  However, the little jets are either 
too shallow for my extractors to get enough grip into the brass, or they 
are too small for any jet.

Has anyone encountered a similar issue?  How did you get these stubborn 
characters out?

Thanks for your help,
Ben Wagner