'73 Vette Q-jet question----Eric? Help!

[Verne_Frantz]

Well, I got myself into something to help a friend who did me a favor and I'm rebuilding his '73 Corvette Q-Jet. I ran into something that might indicate that the carb might have mis-matched components, namely the lid. When I got the carb it was missing the link that goes from the vacuum pull-off to the secondary air valve on the air horn. Every pic I"ve seen of a Chevy Q-Jet shows a piece of linkage on that valve with a slot in it for the link, but this piece has a lever with a single hole (like a Buick perhaps).
He complained that when he reached 4-gear under WOT that it just fell on it's face. Well.....no wonder, it was running on a little 2-bbl!!! The secondary air valve never opened!
So, my question (and I hope Eric can help, or anyone else who has a knowledge of that correct carb)is ............... is that carb supposed to have a slotted lever on the shaft for the secondary air valve or a captured single hole? IF it needs to be a slotted type, can someone provide a source for the correct lid?
I should just stick to 4GCs and AFBs which I can do in my sleep! I want to make this thing as nice as it can be to return the favor for him putting up all the shelving in my new shed.

Sure would appreciate some guidance here........

Verne

[VintageMusclecar]

Verne;

Any chance the carb might be a parts store reman? That sounds exactly like something the mass rebuilders would do.

Does the pull-off (i.e. vacuum break) have a hole or a slot for the air door rod to attach?

Get me the #'s on the side of the carb if you would so I can see what's supposed to be on there and we'll go from there.

Eric

[Verne_Frantz]

Thanks Eric. The pull off from the vac break is slotted. I'll have to get you the number tomorrow.
This is what I started with. Glad I took pics as it was.




Verne

[VintageMusclecar]

Verne;

That's actually the correct combination. There will either be a slot on the air door shaft or the vacuum break, but not both. Since you said the carb was/is missing the vacuum break rod all together, I'm led to 1 possible conclusion;

The secondary air doors are opening, but MUCH too quickly since the vacuum break isn't connected (the vac. break controls how quickly the air doors open along with the air door spring adjustment).

Hence, bog city.

If you'll notice, the carb is missing the secondary lock-out lever as well, so we know the secondaries aren't being held closed by that.

Get me the #'s from the carb and I'll see if I can't scare up an air door rod and a secondary lock-out lever for you. Check the vacuum break to make sure it still holds too.

How quickly do you need to have the carb wrapped up?

Eric

[WILMASBOYL78]

Just another reason why this guy is the best in the business...always trying to help

[Verne_Frantz]

Eric,
I checked the vac break and it holds good. I'd like to get this done asap because Spring has sprung here; it's in the '60s and he wants to enjoy his car.
The numbers are: main body 7043202 FS with a 0253 date (guessing that's late '70 for a '71 model, and I think it's an auto carb rather than a 4-spd)
Throttle plate # 7881
Air horn: cast inside in a circle 4924

Here's a pic of the other side. I'm not doing any "cosmetic" work on it other than cleaning. It's an unrestored car and he wants to leave it look that way.



Any help you could offer will be greatly appreciated. Oh, by the way, the secondary air valve seems to have a pretty substantial amount of spring tension on it.
Verne

[VintageMusclecar]

Verne;

I have the air door rod and the secondary lock-out lever ready to be boxed up for you.

Give me a call sometime today and I'll get these on the way to you.

Eric

*EDIT*

I just noticed in the pic above this post that there's no curb idle screw in the carb body--is that missing as well, or wasn't it re-installed when you took the pic?

[Verne_Frantz]

Eric,

I don't think there are any other missing pieces. I just haven't put it all back together yet. I'll be in contact soon. Thanks.......

Verne