Quadrajet secondaries not opening

[itsnicyo]

Hey guys, I've been dealing with this issue for some time now.. My secondary throttle blades are not opening! Any help would be appreciated, I've included a video so you can have a better understanding.

[youtube]xa5WfzkgF3w[/youtube]

 

[techg8]

Quadrajets typically have a secondary lockout lever that will stop the secondary throttle shaft from rotating when the choke is activated. If the choke gets out of adjustment, or if the lockout lever gums up, this can cause your problem.

It is what I would check first.

You can find the lockout lever on the passenger side of the Qjet, mounted on the rearmost choke stud, behind the choke housing. it kicks backward and engages the secondary shaft pin when the choke is on.

I am assuming you have an E4ME style Quadrajet.

by the way i cant see a video?

 

[awdblazer]

on my quadrajet it takes a lot to open the secondaries

 

[BPTTONE420012]

what engine is it on? and which qjet is it? QJets have a MAX airflow of 750-800 cfm... the secondary side of the Qjet opens according to the airflow requirements of the engine, the same qjet can be used on a ton of engine sizes... The basic 750 QJet is used from 231ci to over 400ci - the secondary air valves open ONLY as the engine breathes. on a stock 350sbc the air valve will NEVER open all the way because the 350sbc has no use for more than 600 cfm or so

 

[darbysan]

If you are testing it in a garage setting, the secondaries will likely not open- not enough load. The secondaries are actually way down in the carb. The part you see on top are the throttle blades. They open based upon Vacuum in the manifold. That being said, if your linkages are up to snuff, and the choke is turning off when warm, it may be that your Air Horn has been warped. This is the top part of the carb, and if the screws are over tightened ( like maybe the gasket is leaking), you can warp the area around the rear throttle blades, causing them to "stick" closed. I found this issue on mine, and corrected it using a small round file carefully around the edge where it was sticking ( carb removed from engine, of course). It can also be that a PO has tightened the spring that balances the opening of these throttle blades, but that is less likely ( it is really hidden, and a pain in the a** to get to).

 

[itsnicyo]

Not sure why that video isnt working, let me know if this link works. http://youtu.be/xa5WfzkgF3w

The lockout tab isnt blocking the blades.. and im aware of the vacuum ran flaps on the top but im talking about the secondary blades. If the video works now you should have a better understanding.

 

[GP403]

Not sure why that video isnt working, let me know if this link works. http://youtu.be/xa5WfzkgF3w

The lockout tab isnt blocking the blades.. and im aware of the vacuum ran flaps on the top but im talking about the secondary blades. If the video works now you should have a better understanding.

fixed the video, all it needs is just the video ID, (ie the xa5WfzkgF3w) NOT the rest of the url...

 

[itsnicyo]

Bump?

 

[G-Body_Vet]

Visiting Cliff's site may be of help if you haven't looked there yet. If you need a q-jet answer that's probably one place you'll find it.

http://cliffshighperformance.com/simple ... /index.php

 

[techg8]

Attaching a pic

Look on the inside of your primary throttle arm.

When you rotate the throttle arm back, opening the primary throttle blades, there is a "finger" (pencil on left in pic) that rotates with the arm and at a certain point it should contact another tab (pencil on right in pic) that is connected to the secondary throttle linkage.



If the throttle arm "finger" has broken off or is out of adjustment, OR if the secondary tab is broken off or out of adjustment it can effect when the secondaries open....even to the point where they barely open.

snap a pic of this area on your carb.

EDIT: looking at your video closer, it appears that the "finger" may have broken off? hard to tell