carter quadrajet
Thread Starter
Instructor
Joined: Sep 2006
Posts: 158
Likes: 1
From: Blaine Minnesota
carter quadrajet
I have a Carter quadrajet on my 78 automatic and it bogs down when I jump on it. I have the paper from Lars, but it covers Rochester carbs. He references a secondary airvalve adjustment screw and I cannot seem to find it on my Carter. Is there one on my carb? If not, is there some info on Carter carbs that can help me cure my bog? Thanks
Drifting
Joined: Sep 2004
Posts: 1,959
Likes: 1
From: North Bend Ohio
Carter Quadrajets are exactly the same as Rochester Quadrajets. Carter simply helped when Rochesrter couldn't keep up with demand. Get a book that identifies the parts of the carburetor.
BigBlockk
Later.....
BigBlockk
Later.....
Thread Starter
Instructor
Joined: Sep 2006
Posts: 158
Likes: 1
From: Blaine Minnesota
That's what I hear, but when I look for the screw to adjust the secondary spring windup I can't find it. Does anyone have a picture of it's location on the passenger side of the secondaries as is stated in Lar's paper? Thanks
Melting Slicks
Joined: Mar 2007
Posts: 2,100
Likes: 12
From: Frederick Maryland
As already said, the Carter Q-Jet is identical to the Rochester. GM liked to have more than one supplier...not only to keep up with demand, but also as a hedge against strikes at the primary supplier. That way they wouldn't have a complete interruption of supplies.
Drifting
Joined: Sep 2004
Posts: 1,959
Likes: 1
From: North Bend Ohio
DO NOT LOOSEN THE SET SCREW BEFORE YOU HAVE CONTROL OF THE ADJUSTMENT SCREW! THE ADJUSTMENT SCREW MAY UNWIND!
BigBlockk
Later.....
Tech Contributor
Joined: Aug 1999
Posts: 14,370
Likes: 6,364
From: At my Bar drinking and wrenching in Lafayette Colorado
As the others have said, the Carter Q-Jet is identical to the Rochester Q-Jet - they even carry the same part numbers. The secondary airvalve adjustment screw is there - it's right under the secondary airvalve lever.
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From: A 12/8 man in a 4/4 world
if you want to be adventurous,
either remove the carb or just the air horn.
Then hold upside down. you will see the spring, screw and allen screw.
If you flip the secondary butterflies, you will see the shaft move.
there is a pin that tightens against the spring.
Once I did this I had a better understanding of the system
either remove the carb or just the air horn.
Then hold upside down. you will see the spring, screw and allen screw.
If you flip the secondary butterflies, you will see the shaft move.
there is a pin that tightens against the spring.
Once I did this I had a better understanding of the system
