Rooster Feather

The carburetor is sticking when I let off on the accelerator. If I blip the throttle or use my toe it will return to idle. It does however act as a cruise control when going down the road (dangerous, yes). I have read other threads concerning this very problem. They suggest unhooking the linkage from the carb to make sure that the linkage is not causing the problem. I have done that. They then suggest that the culprit maybe the butterfly hanging up on the gasket. My question is this.... when they say gasket are they referring to the metal shim that is directly beneath the carburetor? Because I have it directly below the carb, then the hard spacer, then the paper gasket. Just making sure I have it correct? Does that shim sometimes interfere with the butterflies? If so, do you just file it back with a file?
Craig

johngandersonjr

I had the same issue recently. Found my return spring was too weak.

Frankie the Fink

Yes, unhook the linkage and try it...that will eliminate silly things like the nylon slider plate on the back of the gas pedal worn down or the linkage rubbing on the ignition shielding.

Asking advice without stating the type of carb won't get you the best help.
They all have their idiosyncrasies...

Rooster Feather

Sorry. Carter AFB. Pulled carb and no rub on the shim. However with all the linkages loose the carb gets a little stiff when it is 90% closed. Called Chicago Carburetor, they did the restore, and they said send it back. Also noticed a burn spot under the throttle linkage on the manifold. Turns out it was spitting fuel out when you press on the accelerator. Chicago Carb was supposed to put bushings in if there was slop in the rods. I think this one got by them. So shipping it back to them today. I'll post results.

tach drive 61

the linkage could hang up on the ignition shield as well

Frankie the Fink

Uh yeah. Like I said in post 3 above. The AFB has some unique issues. Sometimes that peened on throttle linkage plate gets loose and won't completely close the throttle plates. With the linkage removed if you can push forward on that plate and the car returns to idle that could be the issue.