Fix the mix ( carb trouble)
 

My '31 pu runs a Zenith carb. For the most part it runs fine, especially when cold. However, lately I've noticed a couple of things. When the GAV is set for a smooth idle ( open about 1/4to 3/4 turn) the engine runs lean especially at top rpm. While running, if I open the GAV another turn the motor haas mor power, but loads up at idle.
When I first got the truck I gave the carb a quick cleaning, and replaced the jets with Snyders rebuild kit. May be time to turn it over to a meticulous rebuilder. You know, beading & flow tests. What do you think?
Any recommendations?

Re: Fix the mix ( carb trouble)
 

Sounds to me like it is time for a good rebuild of the carb. By rebuild I mean fully bead blast, then clean every passage by hand, replace any and all worn parts, including make sure the throttle shaft is tight, flow test, etc... Do not forget to use a new gasket between the carb and the intake manifold.

Re: Fix the mix ( carb trouble)
 

Bro,
Are you ideling too fast? At a slow, proper idle, the GAV will NOT affect the idle. The GAV is just an extra high jet to supplement the fixed high speed jet when extra fuel is needed, depending on weather temp, altitude, humidity, etc.
Chief taught me, on a warm engine, run steady in 2nd gear at 20 to 25 MPH, adjust GAV for best running. THEN if it runs well from cold start on up to warm at that setting, just LEAVE it alone & don't DIDDLE WITH IT!!
Not tryin' to sound smart assed, but that's How he told me, only he used much STRONGER words, that I won't type here!
Just SLOW the idle WAY doooown to 400 RPM or so, they sound SOOOOOO GOOD. Remember, GAV & idle circuits are whole different animals.
Chief was old drinkin' buddies with Bill Ogan, our small town Ford Dealer & had full run of his shop & learned a lot of crap, wish I could recomember ALL the stuff he told me. (SIGH!) Bill W.

Re: Fix the mix ( carb trouble)
 

That's my vote! I would go one further and look for another carb to rebuild. This way you can still enjoy your car in Ca. weather and put the new restored carb on when done then repeat with the one on the car now so you have a spare or one to sell.

Here is a comprehensive work sheet so nothing is missed;

Re: Fix the mix ( carb trouble)
 

Re: Fix the mix ( carb trouble)
 

If you got new jets, I would get them checked for correct diameter holes. A set I bought had the idle jet way too small hole & would not idle. Actually, I would find some old original jets , make sure they are clean & dong them in.
But then Im a ''foreigner.''

Re: Fix the mix ( carb trouble)
 

Yo, Tudor Buddy,
I'm a FOREIGNER too, came to Sunny California from Oklahoma. Mamma also told me I was, English, Irish, Dutch, German, and 1/8 Pawnee Indian! Where's my OIL MONEY??? Bill W.

Re: Fix the mix ( carb trouble)
 

Yeah, Bill, the idle is quite slow. I've hardly ever fiddled with the GAV, but the other day I opened it a bit to give me some boost on a hill. Anyway, you're right. The idle should not be affected. But it is. That's my quandary.
Thanks for the input gents.