'65 Carter AFB - choke valve attaching screw

[Oliver S.]

Hello,

today I've discovered that one choke valve attaching screw of my original Carter AFB ('65 Corvette, 300 hp) has broken off. Since I've been owning the car for one year and I'm new to the active hobby I can't say if this has happened during my possession or before. At least I haven't seen the head of the screw in the (still mounted) carb and the metal on the breakage isn't shiny (so it doesn't seem to be new).
Now I've got a few questions:
1. Is it unwise to drive it in this condition?
2. I live in Germany and now I'm asking myself where to get the screws. For that it is important if the thread is inch or metric. I suppose the latter one.
3. In order to access the remaining thread I intended to remove the other screw and then the choke valve. Then remove the thread with a pliers and reattach the choke valve, all with the carb mounted. But the screws are split at the tip. How are they to be handled before removing them? Is this procedure correct or am I missing something?
Thanks in advance.

Oliver

[Oliver S.]

Re: '65 Carter AFB - choke valve attaching screw

What I meant with my previous question regarding the removal of the intact screw is:
It can only be turned easlily 1/4 rev before it gets harder due to the split at the tip. At this point I stopped. Should I apply more force or try to bent the tip together with a pliers.

Regards
Oliver

[Christopher R.]

Re: '65 Carter AFB - choke valve attaching screw

What is the "choke valve attaching screw"? Can you post a picture?

Are they the little brass screws that hold the plate onto the rod? Are there 2 plates on the top of the primary carb throats? Attached to a rod that passes through the carb throat at the top? 2 screws per plate?

If so, I wouldn't work on them while the carb is mounted. All the debris from your work will fall down the carb throats and into the engine on start up. It's easy to remove the carb, and then do your work on a bench. This is also fussy precision work. You'll want to be able to have good access.

I believe those little brass screws can be found mostly in hobby shops. I believe the ends are split or peened over, so that when you go to remove them, you'll break off the heads. I don't know how to get them out without breaking off the heads and then drilling the bodies out. You'll need a drill press because this is very precision work. The thread is fractional inch. But because it's so small, and you'll be drilling, metric would probably work too. Ask a machine shop how to do this job.

You'd probably be OK operating the car leaving this plate attached with only 1 screw. But, that'd make me nervous. If that 1 remaining screw fell off when the engine was running, the plate would be ingested into the engine.

You might consider removing the last screw and leaving the choke valve out. The way we use these cars now, a choke is not essential.

[Clem Z.]

file the "split" end flush with the shaft and when

you reinstall it use red locktite or maybe some of these corvette parts places sell that screw.

[Oliver S.]

Re: '65 Carter AFB - choke valve attaching screw

Hello,

here are 2 pictures showing the broken screw (red arrow pointing to remaining thread):

http://www.imgwelt.de/show.php?code=8V235C69VDU

http://www.imgwelt.de/show.php?code=L0XRW743485 (open choke valve)
The one remaining screw is fine/tight, the remaining thread is tight.

Regards
Oliver