Autolite 4100 C6ZF F

[messmoremh]

Hard starting, suspect leaking carb??? Pull top cover off and one bowl is down 3mm. Carb thoroughly gone through with missing weights replaced and bad emulsion tubes replaced. Still a very hard start when cold. Any Ideas or perhaps what model Autolite 4100 could be used as a replacement carb body. Any great Carb guys in western Washington State? Thanks for any help.......

[67350#1242]

There are 2 places where a 4100 can leak - accelerator pump and power valve.  If fuel is leaking out of either cover it will be pretty easy to spot.  The covers also often warp due to over tightening and will be difficult to get to seal without straightening.
If acc. pump diaphragm is bad it will leak out when throttle is pressed.
Bad power valve will allow fuel bowl to drain down into the manifold and will empty fuel bowl when parked - this will cause hard starting due to either flooding or empty fuel bowl depending on how long the car has been shut off.
If you cant find any leaks on the outside (or if there is no obvious raw fuel smell) I would strongly suspect power valve - even new ones can be bad out of the box.