Cliff's Quadrajet Parts and Rebuild Kits

Quadrajet Problem Solving => Diagnose a Quadrajet carburetor problem => Topic started by: Dave77vette on July 11, 2009, 04:52:03 PM

Title: Wide open throttle at startup
Post by: Dave77vette on July 11, 2009, 04:52:03 PM

I just rebuilt my 77 corvette Quadrajet with cliff's rebuild kit and slapped it on my 383 stroker i just built.  I converted from hot air to electric choke.  I used cliff's kits and the third recipe from the book.  Im lost on what to do.  Everytime I start my car, i have to hold the primary air flap shut or the rpm's automatically jump up to about 6500.  ???  Does anyone know what im doing wrong?  I backed out mixture screws 4 turns, and my APT screw one turn.  My sidepipes are blowing some eye burning black smoke.  I haven't been able to time it with the light due to my problem with getting it to idle.

Please, any advise will help, Im lost ???

Title: Re: Wide open throttle at startup
Post by: Cliff Ruggles on July 12, 2009, 04:22:31 AM

Check the baseplate to make sure the primary and secondary throttle plates are closed at idle.

To run 6500rpm's, the carburetors throttle plate(s) would have to be open considerably....Cliff

Title: Re: Wide open throttle at startup
Post by: Schurkey on July 12, 2009, 07:05:22 AM

Wildly out-of-adjustment fast idle screw?

Fast idle mechanism jammed or binding?

Lack of throttle return spring?  (got me last weekend...)

Linkage for secondaries caught/binding on something?