The Stovebolt Site Forums The Shop Area Engine Shop Carb

Is there any other carb I can use on my 51 gmc till I can get another zenith to replace my original zenith I have already tried hhaving mine rebuilt but it didn't take so I am going to replace it but a new one is very expensive just wondering if I can use another while I save for a new zenith

What "didn't take" when having your carb rebuilt?

To whom did you send it for a rebuild?

51 GMC 228 engine?

Post a want ad in the Swap Meet.
You might as well look for a Zenith carburetor from a 228?

Those single barrel Zeniths are some of the easiest to rebuild and most reliable carburetors on the planet!

Are you positive the carburetor is the problem?

What kind of issues are you having?

Jon.

Yeah the rebuild didn't take the throttle shaft is worn out it is sucking air still runs only half to 3/4 choke the guy's name that rebuilt is Hal houghington he's out of New York it cost a lot of money and if I do it again I will have paid for a new carb

Carbking yeah I'm pretty sure that's the problem cause I can't get any adj out of it

Does Hal Houghington guarantee his work?

Is it Hal Houghton?

Hal Houghton is his name it's been to long now so I have to figure out what to do

As far as my limited experience goes, his price is exorbitant. If he missed seeing a loose shaft, that is shameful.

Any used carburetor you buy should be rebuilt. You might as well get a used Zenith for a 228ci GMC and get it rebuilt,

If you need recommendations for reputable carburetor rebuilders, Carbking is a member and he might still be rebuilding carbs. I also know two other experienced Zenith (and other) carburetor rebuilders.

Thank you I kinda thought so myself but it really sucks cause I spent like 350 + dollars and I am no better off then when I sent it to him

I wonder if there is a bushing kit I could use to fix the worn out throttle shaft if so do any of yall know

thanks michael

Tim - thank you, but carbking is no longer rebuilding carburetors, as the demand for rebuilding kits keeps him busy!

Michael - there are three possible reason why the carburetor is sucking air by the throttle shaft:

(1) the throttle shaft is worn
(2) the throttle body is worn
(3) both (1) and (2) above

The design clearance (you have to have some clearance or the shaft would stick when it got hot) is 0.004~0.006 inch. An additional 0.003 is not an issue. So you can use a dial indicator to determine the current clearance. If it does not exceed 0.009 inch you are OK. If the clearance is 0.010 or more, you will have idle issues; BUT it probably is fixable.

If the clearance is 0.010 or more, CAREFULLY grind off the back side of the screws holding the throttle plate to the throttle shaft(FAILURE TO DO SO WILL CAUSE MORE PROBLEMS!!!). Then remove the screws, followed by the removal of the throttle plate and the throttle shaft.

Use an inside micrometer to measure "out-of-round" of the throttle body, and a micrometer to measure out-of-round of the throttle shaft.

IF YOU NEED BUSHINGS AND YOU ARE NOT A MACHINIST: take the throttle body to a local machine shop. Bushings are available.

If you need a throttle shaft, you will need the inner number on the round tag riveted to the carburetor. A new old stock throttle shaft is probably available.

$350. is NOT excessive for a quality rebuild, but I WOULD expect a quality mechanical rebuild for that price. Still would not get you a "show quality" cosmetic restoration.

If you have more questions about the procedure - (573) 392-7378 (9-4 Mon-Tues central time).

Jon.