Secondaries dont open, misses 2nd gear. Vacuum?

[techg8]

TechG8,
Is this the lockout in the pic circled in yellow?
How do you remove this, any secret to its removal?
There is no hang ups on the throttle plates. They just won't open unless I use my finger and push down on the lever (as in my original post pics).
I will check the modulator connection. As for now, I hear the kids awaking from dreams of sugar plumbs.
Have a merry Christmas G Body Guys.

no that is the choke cam, and it provides the larger throttle opening on cold starts for your choke fast idle. You need that piece.

There are three posts that are supporting the choke bracket on the side of the carburetor. the rearmost of the three will have the lockout lever on it, hidden behind the choke bracket. Its function is to swing rearward and catch the lockout pin on the secondary throttle shaft on cold starts.

to remove the lockout lever you must loosen the choke bracket screw enough to pull the bracket far enough away from the carb body to slip the lockout lever off its pivot.

Also to clarify, when I refer to throttle blades I mean the ones in the baseplate of the carb. The secondary plates in teh air horn are called air flaps.

If the air flaps are not opening its likely because the throttle plates are not opening - locked out or jammed .

 

[papastoy83]

While rebuilding my original CCC Qjet , I found that the air valve was sticking to the body. Was a small amount of casting flash. Removed it with a file. Check to make sure the air valve is moving smoothly and not sticking anywhere. Also, check the air valve door spring for smooth operation.

 

[KILLSHOTB]

I removed the lockout with little effort. I also pluged the port that goes to the air cleaner (I had it connected to manifold vacuum). So right now, I only have manifold vacuum going to the transmission and to heater controls.
What I hope to have accomplished is to get that head jerking acceleration when you put the pedal to the floor going over 40 mph. Now this type of acceleration is possible among any 4 barrel car, and they all have lockouts as would a stock q jet. So the only thing is the vacuum line I plugged that may correct any problem. Unless the lock out was not working correctly and removing it would take it out of the equation.
I don't know, have to wait till spring to test it.

 

[Bruce Compton]

Your car and the underhood look nice Mike. 🙂

 

[gbondo57]

On the TH350, it sounds simple, but when I messed with the vacuum tube on the manifold, i pulled it off the modulator underneath. The kickdown cable is needed if the modulator is not adjustable. Try looking into the vac port on the modulator with a flashlite see if a screwtip is inside. If so, it's adjustable. Good luck.