APT setting in a Quadrajet ????
Thread Starter
Instructor
Joined: Jan 2010
Posts: 129
Likes: 4
From: Perth western Australia
APT setting in a Quadrajet ????
Decided to rebuild my quadrajet with a Kit from Cliff Ruggles, striped it down and removed the APT adjustment screw with taking note of the original setting 
Any suggestions as to how far I should screw it back into or how many turns back out .
Andy
Any suggestions as to how far I should screw it back into or how many turns back out .
Andy
Safety Car
Joined: Oct 2007
Posts: 4,364
Likes: 1,724
From: Seattle Area Washington
Not sure what primary rods the 79 has, my 77 had 52K primary rods. Before I dissembled I took a measurement from the top of the main jet to the top of the primary rod in the hanger. My measurement was 1.9935" with APT pushed down. I also used a Ciffs kit and he suggested I go to .44 rods. My measurement with the .44 rods is 1.9455. I used Lars diagram in determining the depth of primary rod into the main jet. A 10x jewelers loop is a must have to see this. In the hanger, make sure both rods are equal in measurement.
Last edited by bmotojoe; Aug 20, 2016 at 12:04 PM.
Le Mans Master
Joined: Jul 2006
Posts: 8,117
Likes: 104
From: charlotte north carolina
Adjust the screw height so that the collar of the rod is just below the top of the jet bore. Use a black magic marker to highlight the collar so that you can see it drop into the jet bore. There is no "set" number of turns. After the engine is running, a fraction of a turn will raise the rod or lower it enough to allow final adjustments.
Tech Contributor
Joined: Aug 1999
Posts: 14,373
Likes: 6,370
From: At my Bar drinking and wrenching in Lafayette Colorado
An adjustable power piston should be set up so that about .020”-.030” of the inner brass sleeve is visible above the top inner lip of the plastic retaining collar.
Lars
Lars
