Accelerator pump issues after installing rebuild kit

[dibbons]

This has happened three times in a row now, with three different carburetors, you know, the '60's and '70's Carter two-barrels used on small block Mopars. When I am done cleaning, checking, and installing the carbs, the accelerator pumps just don't want to pump anything more than a micro-drop of gasoline. My vehicles hesitant for a moment when accelerating from a stop, and then they take off normally. ('65 Valiants and '72 Satellite Sebring Plus)

I know there is a certain size check ball that is placed in the bottom of the well, I know one can adjust the pump shot, and I know to lubricate the leather with oil, tranny fluid, gasoline or something beforehand. I have posted this problem before and even sent a message to Slant Six Dan, but I have never received an answer. Am I the only one with such bad luck? Thank you for listening and responding if you have some tip. P.S. I actually found a 1973 NOS Carter carb online (had never been installed before) and after changing out all the gaskets in that carb, I STILL had accelerator pump failure.

 

[66fs]

Is it the pump or check valve? Remove the nozzle housing and add fluid to see if the ball seals the passage. If the fluid does not leak down, look elsewhere. If the check valve is bad, you can take an extra ball and install it, then take a hammer and punch and carefully tap it to get a good seal. Throw that ball away and install a new ball. I usually take a small screwdriver and "spread" the leather out before oiling it. Also polish the pump bore with WD-40 and some 600 wet or dry sand paper.

 

[RustyRatRod]

I wouldn't use a leather pump in a frikkin thing anymore. Ethanol will dry it slam out. You should be using ethanol friendly rubber/neoprene pumps.