Sticky Throttle C2
 

Re 66 300HP/327

One of my winter projects was to replace the nylon wear pad on the back of the accelerator pedal. LIC sells this part amazingly. Took a long drive today and now I have a sticky throttle, i.e., poor man's cruise control, pedal stays in place when I lift my foot.

Upon returning home I put a little grease on the pad and with a mirror I noticed the curved portion of the accelerator rod rubs the nylon pad very near the bottom. Is my accelerator rod bent? Wouldn't you expect that wear area to be nearer the center of the pad?

Also I checked my throttle return spring. The bracket near the thermostat has an upper and lower hole. I moved it from upper hole to lower hole. My assembly manual UPC 6/D2 just shows a single hole??

Randy

Un-hook the rod going to the carb and see if you can isolate where it's hanging up.

Two other things to check:

- floor mats catching on gas pedal?

- throttle linkage hanging up on breather tube under the air cleaner base?

Could be the pivot that passes through the firewall. I believe it has plastic bushings that are prone to wearing out.

If this all doesn't get it
 

i have seen many a carb installed not quite in alignment where the throttle butterflys were hanging up on the intake gasket or intake top! i like the holley sphericals on my linkage set up, and i have seen many a weakened return spring!

Could be the pedal is sitting too high. I found 2 blocks/spacers under the gas pedal when I re-carpeted.

Gary

If the nylon pad is all you changed and the throttle didn't stick before - well what can I say ? Anyway - check all of the items mentioned above as well as the top of the carb if you have an AFB -- the accelerator pump shaft can wear down the guide lugs over the years and cause sticky operation !

Sticky Throttle
 

Good tip. When I redid my carpets in 2007 I noticed the driver's foot well had some fiberglass damage which I repaired. Maybe I am not to OEM dimensional specs so I removed the 1/2" spacer I made.
Curious why GM designed a spacer here.

Also no apparent issues with linkage at the firewall. However I did notice that if UPC 6/D2 is correct my throttle linkage was on backwards. Cotter pin should be outboard and swivel should be inboard. That will change geometry slightly.

Thanks to all who responded

Randy

Thanks for the tip Frankie but I have a Holley. BTW I just got around to adding nylon washers under the carb mounting nuts to cut down on heat conduction to the carb. One of your many tips

Randy

I chased a similar problem a while back. it turned out the choke rod was too long where it connected to the choke and was hitting the carb body:cheers: