I am back working on my D4-5T.  I have been having problems with the Pony Carburetor, 8B3917.  I pulled the Carburetor a couple of years ago due to the amount of fuel leaking past the 1/8 NPT threads on the fuel inlet on the float bowl cap and the looseness of the 1/8 PT elbow on the bowl breather.  I have known that the fix for the loose pipe threads was going to be an application of J-B Weld on to the threads to compensate for the worn threads for years.  I had another application that need J-B Weld and I liked over the instructions looking for material that J-B Weld would not stick to to use as a mold for forming the threads into the zinc castings.  I ordered some Poly Propylene fittings from McMaster.  I purchased a pipe to compression fitting to screw into the cover allowing me to align the fuel hose in any direction I might like without being limited to the street elbow the had been screwed into the top cover.I reinstalled the carburetor on to the tractor and installed a new fuel filter  and fresh E-Zero gasoline.  No fuel leaks.  I got the pony to run but only at idle.  I have pulled the carburetor and watched the five YouTube videos by Squatch253.  I disassembled the carburetor and blew out alll the passages with B-12.  The low speed jet may have had on obstruction but otherwise the passages are clear.My question is on the spring loaded lever assembly, 9B4883.  Mine does not appear to be functioning.  I have tried to pull the drive pin assembly out of the housing.  In Squatch253’s video that all came apart.  I don’t have enough experience with one of these carburetors to know what is normal.  The parts book shows no serviceable parts other than the assembly.  Am I missing something?This is the same carburetor I posted the throttle shaft replacement on in 2007.

I just check my spring loaded lever assembly 9b4883 and this pine can not be removed and she look like just on the outside housing because the inside boushing is turning when you play with the lever

Did you look in the parts manual to see what kind of fitting the carb inlet takes. Chances are that it isn't an NPT thread but rather a ferrule and collar of some sort.My 17A had an NPT threaded fitting which leaked and my carb guy says he sees split cast iron inlets due to using NPT threads.

The TU4C carbs have  1/8" npt inlet threads.

Having just crossed this bridge I'm completely certain that the threads are pipe thread. Over tightening can crack the bowl.