Hard to turn Gav

Russ/40

Well-known member
The Gav in my truck is hard to turn. Any suggestions on how I can free it up and make it smoother to turn? It is correctly aligned with no binding outside the carb.
 
Disconnect the rod from the carb and loosen the nut or screw on the choke butterfly and remove the outer sleeve from the GAV and drip a bit of light oil down into the actual needle, then reassemble backwards.

If you really feel adventurous, remove the whole needle and do a little light oil on the threads.
EDIT: IF you really want to remove the GAV valve itself, an 11mm deep socket will fit, otherwise you may strip off the corners if you use a 7/16

It ain't brain surgery. Because of the crap gas they get a bit dried out is all.
 
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Laughed when I saw your post. I have the exact opposite - set the GAV after starting then notice as I drive that it is opening up as I go along. Any ideas of how to stop this??
 
In addition to Rawhide Kids entry level suggestions. (which is where you start.)

A lot of either the original and aftermarket GAV parts are not made to Ford Spec. Mostly likely you (or someone) have found and used "mis-matched" GAV parts: i.e. the needle too big in diameter below the thread or the GAV bushing too small in the hole to pass the needle easily, or too robust in the "fingers."

This is what happens when parts are sourced from different suppliers.

The point of the fingers and springclip is to create friction against the needle and prevent its movement due to engine vibration. So yes - there should be "some" resistance to turning.

The solution is not hard. You can remove the springclip entirely and you may find the fingers allow passage of the needle but sufficiently constrain it so it doesn't turn.

Or, following that thought - try putting an ice pick in between the fingers and "spread" the fingers slightly bending them outward. Be advised to go slow. As a younger man I did this and ended up breaking off a GAV bushing finger - but I put it back together with the springclip and minus the finger - and now the tension seems "just right."

No, it isn't brain surgery. But the easiest minds to know are the "simple" ones.

Edit: Note to Jim M - now that you know how it works - you can take steps to make it happen.

Edit 2: Ford dramatically improved this arrangement with the Model B carburetor. There the GAV bushing is simply "pressed" into the housing - but underneath it is a washer (the needle passes through) and a spring which bears the washer against the needle preventing its movement.

Joe K
 
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I try to leave the clip at the end of the GAV housing in place, but expand as mentioned above gradually until I get an acceptable result.
Or I start trading GAV needle valve shafts until I get an improvement.
The aftermarket replacements have this issue.
Bob
 
Disconnect the rod from the carb and loosen the nut or screw on the choke butterfly and remove the outer sleeve from the GAV and drip a bit of light oil down into the actual needle, then reassemble backwards.

If you really feel adventurous, remove the whole needle and do a little light oil on the threads.
EDIT: IF you really want to remove the GAV valve itself, an 11mm deep socket will fit, otherwise you may strip off the corners if you use a 7/16

It ain't brain surgery. Because of the crap gas they get a bit dried out is all.
I sure do not want to start a family fued here but an 11 mm deep socket does not fit perfectly. The only socket that fits is a HAAG 13/32. Ask the man who owns one.
 
I sure do not want to start a family fued here but an 11 mm deep socket does not fit perfectly. The only socket that fits is a HAAG 13/32. Ask the man who owns one.

I have used a six sided 11mm deep socket without problems but I too have a HAAG 13/32" socket.
 
Surprisingly ( on maybe not) I have found the size of the hex on various GAV housings does vary ( and not just through poorly fitting wrenches!) . sometimes it's 11mm sometimes 13/32 sometimes I have to "adapt" a wrench to fit.
 
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