Quadrabog Question
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Instructor
Joined: Sep 2001
Posts: 201
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From: Holbrook NY
Quadrabog Question
I bought a good used quadrajet for my 68. Everything seems to work fine except the secondary air flaps. When I put my right foot down far enough 
the secondaries open up but it is not very smooth at all. What is the proper way to adjust them?
the secondaries open up but it is not very smooth at all. What is the proper way to adjust them?
Race Director
Joined: Mar 2001
Posts: 11,322
Likes: 1
From: Living in the Hartland
E-mail Lars, he is the forum guru for carbs and beer (among other things) and all around good guy, sure he has a tech paper written on the subject he will e-mail ya.
lars.grimsrud@lmco.com
lars.grimsrud@lmco.com
Tech Contributor
Joined: Aug 1999
Posts: 14,375
Likes: 6,375
From: At my Bar drinking and wrenching in Lafayette Colorado
First, make sure your choke pulloff is functional and operable: It should hold a vacuum and fully retract when the engine is running or when you suck on it. If not, replace it. Also, make sure the carb has the secondary airvalve rod hooked up between the pulloff and the lever on the airhorn - I see many carbs with the rod missing.
Next, set your secondary airvalve spring windup: There is a small allen-head screw on the bottom surface of the airhorn, right underneath the airvalve lever. Loosen this screw about 1/2 turn to unlock the windup screw: the windup screw is the slotted head screw that's located right by the secondary airvalve shaft and lever. Using a mirror underneath the airhorn, unwind the airvalve spring until you see the spring lose contact with the airhorn shaft tang/pin. Bring the spring into contact with the pin and wind it up 3/4 turn with the slotted screw. Hold it at 3/4 and snug up the allen screw on the bottom surface to lock the windup in place.
Next, set your secondary airvalve spring windup: There is a small allen-head screw on the bottom surface of the airhorn, right underneath the airvalve lever. Loosen this screw about 1/2 turn to unlock the windup screw: the windup screw is the slotted head screw that's located right by the secondary airvalve shaft and lever. Using a mirror underneath the airhorn, unwind the airvalve spring until you see the spring lose contact with the airhorn shaft tang/pin. Bring the spring into contact with the pin and wind it up 3/4 turn with the slotted screw. Hold it at 3/4 and snug up the allen screw on the bottom surface to lock the windup in place.
Race Director
Joined: Dec 1999
Posts: 11,094
Likes: 990
From: Sierra Foothills CA
Originally Posted by lars
First, make sure your choke pulloff is functional and operable: It should hold a vacuum and fully retract when the engine is running or when you suck on it. If not, replace it. Also, make sure the carb has the secondary airvalve rod hooked up between the pulloff and the lever on the airhorn - I see many carbs with the rod missing.
Next, set your secondary airvalve spring windup: There is a small allen-head screw on the bottom surface of the airhorn, right underneath the airvalve lever. Loosen this screw about 1/2 turn to unlock the windup screw: the windup screw is the slotted head screw that's located right by the secondary airvalve shaft and lever. Using a mirror underneath the airhorn, unwind the airvalve spring until you see the spring lose contact with the airhorn shaft tang/pin. Bring the spring into contact with the pin and wind it up 3/4 turn with the slotted screw. Hold it at 3/4 and snug up the allen screw on the bottom surface to lock the windup in place.
Next, set your secondary airvalve spring windup: There is a small allen-head screw on the bottom surface of the airhorn, right underneath the airvalve lever. Loosen this screw about 1/2 turn to unlock the windup screw: the windup screw is the slotted head screw that's located right by the secondary airvalve shaft and lever. Using a mirror underneath the airhorn, unwind the airvalve spring until you see the spring lose contact with the airhorn shaft tang/pin. Bring the spring into contact with the pin and wind it up 3/4 turn with the slotted screw. Hold it at 3/4 and snug up the allen screw on the bottom surface to lock the windup in place.
