Carter AFB 3720 - removing choke shaft

[Oliver S.]

Hello,

as I posted a couple of weeks ago, the head of one choke valve attaching screw broke off. Beside looking for a correct Carter AFB 3271 I tried to find these screws. Now I've obtained them (although steel and not brass, thus I'll use loctite instead of staking them out) together with a choke shaft.
I heard that in order to remove the choke shaft the top of the carb (bowl cover) has to be removed first. I've got the '63 Corvette Shop manual and the book 'super tuning and modifying Carter Carburetors'. In the shop manual the removing of the choke shaft is mentioned in the section Disassembly - Bowl Cover (p. 6M-9).
When I look at the pics of the design of the 3720 this seems not necessary, but I may be wrong. Any clarification would be helpful.

Regards
Oliver

[Jack H.]

Re: Carter AFB 3720 - removing choke shaft

As you noted, the original screws were staked in place to prevent loosening via vibration. When you un-screw them, it's not atypical for small pieces in the viscinity of the staking to break off. Removing the air horn (or the whole carb) and doing the job on the bench is simply a precaution to prevent stray metal bits from falling into the intake...

Also, go SLOWLY with the removal! It's not unusual for a retaining screw to break (head off body) leaving you in a situation where you have to drill out the screw shank and perhaps re-tap the shaft to accept a larger screw...

[Oliver S.]

Re: Carter AFB 3720 - removing choke shaft

Thanks Jack. I'm going to remove the carb to work on a bench. But since I'm unexperienced I want to remove as few screws/parts as possible. On the other side it's helpful to know when it's necessary, in order to avoid futile attemps that may cause damage and frustration.

[Christopher R.]

Re: Carter AFB 3720 - removing choke shaft

It's not a big deal to take the air horn off. Just a bunch of cap screws and some little cotter pins holding the linkage on. Look at it closely. I believe you'll see that it's easy to take it off.

I also believe you'll find it more difficult to work on the whole carb. The complete carb won't sit flat on a bench. There's linkage that prevents it from sitting flat. Therefore, it can move around when you work on it. The air horn alone is smaller and will sit flat.