wcfb choke piston

[Don Izzo]

The choke piston is binding in the choke housing. I have removed the piston and polished it with very fine sandpaper, but it still binds, causing the choke butterfly to fail to set or stick in the open or closed position. I guess that the bore is either dirty , out of round, or burred. Anyone have any suggestions on how to dress the inside bore for the choke piston. Also, the cross pin that holds the piston to the linkage arm seems to just float. If I turn the piston on end the cross pin will simply drop out. Does this sound correct?

Don

[James F.]

Re: wcfb choke piston-Don

Don, Sounds like you're o the right track. Yes the cross pin will drop out that sounds, sounds corrct. You can drive out the Dennman (?) disc at the bottom of the choke piston bore in order to get a good shot at sanding andpolishing the bore. The sisc would hen have to be reinstalled. Don't think I'd go to this extremw. Sounds more like a linkage bind somwhwee on the litte choke pison system. Possibly the piston pin can be inserted with piston 180 degrees off. Regrds,

[Don Izzo]

Re: wcfb choke piston-Don

I have removed the plug in the bottom of the bore and using a fine sandpaper wrapped aroung a rod of similar diameter, made a few passes to hone out the bore. reinstalled and all seems fine now. I checked the piston function by applying vacume to the small hole on the back side of the housing and the piston comes down with vacume applied. Last question, this carb./choke combo came from a local supplier of Vette parts (in Chicago) without the choke housing slotted disc plate installed. I understand this is utilized to avoid hot spots but is it imperative this be installed or can I run the carb without it?
Don

[James F.]

Re: wcfb choke piston-Don(again)

Dom, Don't think thr slotted plate is imperative. I've seen working chokes with andwithout (most likely lost) them.Pick one up at a flea market sometime. Check to see that the tube in the exhaust maniflold has not rusted itself through(finger on one end, mouth or Mighty Vac on the othr). Your WCFB may have in internal choke passage vacuum leak but since it's been ecenly rebuilt,and little need to go there. Regards,

[Don Izzo]

Re: wcfb choke piston-Don(again)

Thanks Jim, appreciate the help!

Don