Help on Afb , How to remove pin holding air adjustment screw in !

[rodnutrandy]

I have a afb (4312s ) that has a air idle adjustment screw broke off, I think it was tried to back all the way out, which it can't do ,due to being pinned. Now ,I need to get broken needle out . It looks like a threaded hole for the pin, but no allen wrench , Phillips ,or regular screwdriver seems to fit and grab anything. Have any of you ever removed the pin that holds the idle adjustment screw in ? Would appreciate any knowledge on the subject .

 

[coloradodave]

A picture or two might help Randy.

 

[rodnutrandy]

trying to upload

http://media.carcrazycentral.com/data/Photo/carcrazy2_rad93CF_large.jpg click to view Small hole to left where pin is , is hard to see .

 

[coloradodave]

There are no 'pins' holding the idle mixture screws in. They will back completely out of the carburetor if they are turned counter-clockwise. Try taking better pictures of the screw that you say broke and inside the hole. If that's a cell phone picture, try a camera. We'd like to help....

 

[rodnutrandy]

I hate to disagree , but their are pins holding them in, You can see them and the one broken is out against the pin, I have several avs carbs that do not have the pins , but this one does . Give me time to find a way to enlarge picture .

 

[rodnutrandy]

- - - Updated - - -

 

[coloradodave]

So what you're saying is that a pin ran through the mixture screw? So it would have to turn around with the mixture screw? Try and take a close up of the end of the broken screw. I wonder how the screw traveled in and out, unless the bore is larger than the length of the pin.
Is the pin loose in the cavity?
This is really weird...

 

[rodnutrandy]

The mixture screw has a taper , you can back the screw out about 3 turns and than it hits the pin and stops , Someone , might have been me ( had carb for about 30 years ) tried to back mixture screw on out , it broke off . I don't know why Carter did this, but has to be a way to get the pins out. The broke off part is being held by the pin , I can see it , but can not get a good picture to show it. I am using a camera , not a phone . If pins were pressed in , I could reach down mixture hole and pry out, the pin hole is threaded , so needs turned out . I can't believe I am the first one to come across this. Will try for better picture , but doubt it will happen. If I get too close , it blurs the picture , This does show the pin , but not well , it is easy to see where the pins are coming in on the outside of the mixture screws .

 

[coloradodave]

I see the hole where the pin was inserted. Could there be a tiny plug (similar to a freeze plug) that was staked into the hole to prevent folks from messing with it? If so, I think I would carefully drill into the plug and try to remove it with a pick. Then the pin may have a slot or socket head.
Again, I would sure like to see a few pictures of the broken off screw.

 

[rodnutrandy]

Broken off adjuster screw

 

[rodnutrandy]

Dave , I do much appreciate your comments, I too , thought maybe a plug could be over the pin, but cannot get a good enough look to be sure , am afraid if I drill (which will be difficult to stay on small steel pin with aluminum around it) and their isn't a plug , than I have ruined whatever was their to remove it , That is why I am hoping to find someone who has dealt with them .

 

[1962polara]

These pics real suck....I'm sure it has to be a screw driver or Allen key.
How else logically would it come out?

 

[khryslerkid]

I don't know if you looked under the carb base for a hole or a plug that would let you drive the pin out from underneath. I see the pin you are referring to. Wonder why they did such a thing? Do you know what year carb? I bet the other screw acts the same...

 

[rodnutrandy]

It will act same, the carb is a 1967. It fits 440 or the second carb to a 426 hemi. That is why I don't want to mess it up. Could be a popular carb to someone wanting a correct replacement # 4312s

 

[miller]

Don't recall seeing one like that.

But looking at your last pic, at the hole where the broken needle valve was, might be looking at two possibilities. That's an aluminum plug 'under' the threaded hole. Usually drill those, relieving the tight fit, then pulling the plug out. No threads, they just hammer in. But, you would need a new plug to replace it!
Don't mess with those unless you really need to.
The other is, what looks like a small hole at the outer sides of each adjustment boss. Wonder if that's how the pins are installed? Just guessing, but if the opening has been peened a bit, that might be what keeps the pin in place.

 

[rodnutrandy]

The pins are in the small hole, but screw in . I tried phillips, regular screwdriver , and a slew of allen wrenches and nothing seems to bite . That is why I am fishing for someone who has dealt with them . You would think in 47 years , I wouldn't be the first to have remove them ( but than again, Maybe I am the first to break a adjustment screw )

 

[miller]

Yeah, I see what you mean. Try to look up a copy of the manual for that series AFB. Might be your best shot on that pin.

 

[rodnutrandy]

I have a Chrysler shop manual I have had since 1969 , It shows the carb and the pins , but does not mention them , a Carter Book might !

 

[coloradodave]

Randy: Call Ole at Ole's Carburetor Shop in San Bruno, CA. I'm sure he can help you. Tell him Dave from Gotelli Speed Shop referred you. See how his memory is from 34 years ago...lol
www.olescarb.com/

 

[1962polara]

You gotta think it is a normal slotted screwdriver.All the screws on the carb are .
Maybe there's just a buildup of gunk packed into the slot? Some soaked in wd40 then at it! Good luck .