Cliff's Quadrajet Parts and Rebuild Kits

Quadrajet Problem Solving => Dialing in your rebuilt Quadrajet carburetor => Topic started by: Overcamber on April 12, 2016, 07:38:08 AM

Title: Fast Idle adjustment question?
Post by: Overcamber on April 12, 2016, 07:38:08 AM

Hi Gents, got my rebuild back and installed . Great job as expected ! Thanks . Had to turn the idle way down but it works perfect .  Fast idle on the high step is screaming at around 2200rpm . Before I touch anything I wanted to enquire first ? Under the choke housing facing forward I see a small Torx head adjusting screw and it looks like it's turned right in? But haven't tried turning it yet .  If this where I back off the fast idle rpm?
Thanks
Gary

Title: Re: Fast Idle adjustment question?
Post by: 73ss on April 12, 2016, 01:28:44 PM

Yes that should be the one. It should be resting on the fast idle cam.

Title: Re: Fast Idle adjustment question?
Post by: Overcamber on April 12, 2016, 02:40:45 PM

Yes that tamed her down . Thx much . What is a good fast idle rpm . I have it at 1400 and it doesn't sound too bad ? Any thoughts?
Thank you .
Gary

Title: Re: Fast Idle adjustment question?
Post by: Cliff Ruggles on April 13, 2016, 03:30:11 AM

The first step should be pretty high to avoid stalling on really cold days.  Once you "hit" the throttle once most fast idle cams have one or more "steps" so it falls to the next one.  This is the one where you should set the desired speed, high enough so the engine doesn't stall out or load-up while the choke opens.......Cliff

Title: Re: Fast Idle adjustment question?
Post by: Overcamber on April 13, 2016, 04:13:58 PM

Thanks Cliff I'll try that . Haven't been able to leave the yard with it yet due to the snow/salt/sand covered roads but she runs great thus far .  Stay tuned !

Title: Re: Fast Idle adjustment question? very Rich@cruising
Post by: Overcamber on April 20, 2016, 07:33:50 AM

finally had a chance to drive my truck with the new rebuilt carb.  Having a couple issues. First off wide open throttle  is crisp and clear. transition seems great!

My problem is low speed and city cruising speed.  Very light throttle , approx. 1400-1800rpm, 35 to 50 mph the mufflers are loading up and backfiring.  Even at 1/3 to 1/2 throttle. 

Can you suggest something I can try to alleviate this problem?

thanks Gary