Mistake Made with Shipping ring in Carburetor

[marc hildebrant]

Group,

I had replace my carb with new rebuilt Zenith carb about 6 years ago. The car ran O.K. as far as I could tell after I replaced the carb.

I have just replaced the head gasket (other post) and while re-torqueing the head, I thought that I would check over the carb as the GAV seemed to like to be open about 2 turns.

I pulled out the fuel adjusting needle and noticed that there was a metal ring near the point that was in a groove to hold it in place. Checking the Les Andrews book (vol 1, page 1-62) it states to be sure and REMOVE this ring if present. I did, and after a drive the car ran better with the GAV around 3/4 to 1/2 turn out.

What was the purpose of the ring? Why wasn't it removed during the rebuild ?

This ring holds the fuel adjusting needle parts in place.

Marc

 

[Brian T]

Hi Marc,
The ring is used to keep tension on the GAV needle, if you found your GAV open 2 turns it likely got there because I was to loose, with the tension ring removed you make the situation worse, I would refit the ring and check whether it turns with a light tension, see how the engine runs with the valve at a 1/4 turn, --- keep us posted.

 

[Drive Shaft Dave]

Many years ago some of the GAV were made slightly oversize which is why the rings were sometimes removed.

 

[marc hildebrant]

Group,

Many mixed messages.

Why would Les Andrews state that the ring needs to be removed and have it in his book ?

Marc

 

[redmodelt]

Maybe because at the time the book was written, all the needles being made were oversized. The two posters above both are correct, put the ring back on or change the GVA clamp assembly if the ring is lost and see how it works.

 

[marc hildebrant]

Group,

I tried driving the car with and without the ring. I could not tell any difference in the use or "feel" of the GAV. For now, it is re-installed.

Marc

 

[Big hammer]

IF the ring and fingers are to tight, and IF the knob on the rod is loose, you maybe turning the knob off the rod more than turning the gav! Thats a BIG IF but it has happened! You can spread the fingers a little and spread the ring a little.

 

[Mike V. Florida]

Group,

Many mixed messages.

Why would Les Andrews state that the ring needs to be removed and have it in his book ?

Marc

There is more than one error in his book. This error seems to be not explaining why he feels it should be removed.

 

[marc hildebrant]

Mike V.

Yes indeed. If I know why something was done and it makes sense, then I'm satisfied.

Marc

 

[Brian T]

Here are some pics on how I loosen up the GAV, some of the repos are way to tight but can be used, using a awl pressed in to open up the end of the valve a little at a time, keep refitting the needle until you feel a slight bind, --- if it becomes to loose then gently squeeze the ring in a few places with pliars.