The Stovebolt Site Forums The Shop Area Engine Shop carb issues 54 235

Anyone know anything about Zenith carbs?? My 54 Burb has one and I need some parts(gaskets, needle seat, accel pump). Any kit numbers where to get any parts etc. Thanks!

http://www.thecarburetorshop.com/

Jon can help you. He is a member here and offers lots of good advise. You should get some numbers off the carb before you call.

Is there a small metal tag attached to the carb?

There should be a round tag about the size of a dime riveted to the body of the carburetor (if it is a downdraft, probably on the airhorn).

There should be two sets of numbers going around in two circles on the tag.

The outer number is the GMC number which is not as useful as the inner (Zenith) number.

The Zenith number will generally be 4 or 5 digits possibly but not always followed by a letter. The number may or may not be preceded by an O

Examples:

O-9866
O-9866A
9866
9866A
O-12345
O-12345C
12345
12345C

Watch the letters. A's look like 4's; C's look like zeros's.

A good idea to take a pencil eraser to the tag, and then observe with a strong light, a good magnifying glass and a pair of "young eyes" .

Wish I still had the young eyes.

Jon.

understand the young eyes issue!! The number appears to be 14278 D its on a 1954 235 Suburban but their doesn't seem to be a listing for that mfg carb on those years for Chevrolet???? I just need a kit for it.

Zenith carburetors were not standard or optional equipment on 1954 Chevrolet Suburbans (or on any USA 235 Chevrolet engines).

The 248ci engine in 1954 GMC Suburbans used a Zenith carburetor.

If Jon does not know that code, good luck.

I have no record of a Zenith 14278 with any suffix.

Jon.

Well, following Jon's advice my numbers after good cleaning are 11275 D and I sure hope they come up somehow.

GMC used replacement Zenith
14275 and also, 14475

Walker Products lists a rebuild kit 778-608 for a Zenith 11275 and 11275A

O'Reilly Auto Parts
Amazon.com
eBay store

Wait to hear from Jon to see if this is correct. Jon probably sells a kit, too.

Thanks for the heads up on kits-hopefully I'll hear from Jon and maybe he has something.

Zenith 11275 D is one of the Zenith universal carburetors. Consider yourself fortunate to have it, as it is one of the very best single carbs to put on a 235.

And while I try to avoid any advertising in the questions/answers portion of this forum, since others have mentioned me, yes, I do offer a rebuilding kit.

573-392-7378 (9-4 Mon-Tues central time).

Jon.

will call thk you!

Jon need a assembly diagram for that carb....

thks..

As this is a universal replacement, no exact diagram exists; however, a generic diagram for a G.M.C. with a Zenith type 228 (carb type, not engine size) will be close. Try local library and an old truck Motors Manual.

Jon.

I have a rebuild paper for the 28 and 228 if you need a copy.

Its a generic rebuild sheet.

From what I understand the 28 and 228 are basically the same except the idle circuits

An online pdf file for a Zenith Series 28-228.
Right one?


Search Google for,

"Genuinepartscompany/1227942pdf"

Copy & paste it. Use the quotes.
Should be the only Google result.

When you open the file, depending on your Browser,
it may save the pdf file to your computer
incorrectly as 1227942pdf.

Your computer can't open it because the . is missing.

Right click and rename the file, pick a name,
and the name must end with
.pdf

Got it thanks!

Jon where can I get a filter for this carb??
The onw that goes in the upper plate at the inlet??

thks

My truck initially had the inlet filter, but GMC issued a TB to remove them. I may still have it... can post pics but not for sale.

I've never seen one for sale.

This is a very basic and generic sheet and is basically a parts diagram.

The one I have is like 6 pages with step by step directions.

Protip: to get out the check valves use a 3.5 inch drywall screw and screw about 2 turns into it. The pull out. You're welcome

It's the "Instruction Sheet" that is included in Carb rebuild kits that you buy at your FLAPS.

Sorry, I thought this was the assembly diagram that was requested,
since it included..... disassembly, cleaning, reassembly, special instructions,
float level adjustments, and 5 pics showing adjustments,
and also the basically parts diagram with the name of the parts.

Will you post your "6 page with step by step directions"?
It would be very helpful for all when doing the rebuild.




Will you also post your "generic rebuild sheet"?
It should be helpful during the rebuild too.

Thks I'll just forget it. I may just put an inline filter for it.

If ANYONE wants the 28/228 pdf just PM me. I also have a chapter from a manual that's about 20 pages and is much more thorough (jet sizes, performance diagrams etc).

I have the manual digitized and that will be posted at some point on my web site (www.tm9-801.com in the technical publications link) this will be watermarked so restorers know where it came from and can get other publications of interest. The 28/228 pdf will not be watermarked as I have no plans to post it on my site.

Once you have it you are free to post it wherever you like. I don't want the hassle of having to write a web page, alter links on my site, etc etc.

I think I can send files via PM here... if I can I'll do that.

Here's s a snippet from page 1 (its actually 11 pages)

The 28AV and BV and 228-Series Carburetors
are of the single barrel, downdraft type with a
primary and a secondary venturi. The secondary
venturi is pressed into the primary venturi.
These carburetors are of the "balanced" design
in that all air for fuel bowl ventilation and
idling must enter through the air cleaner. For
this reason any restriction in the air cleaner
will have a minimum effect upon the fuel-air
mixture ratio. These models include single
idle, main, accelerating and power jets. The
accelerating pump is operated mechanically by
throttle movement through a link connected to
the throttle lever. The power jet is operated
by engine manifold vacuum.

The basic difference between the 28 and 228
Series is in the idle system. The 28 series
has a single idle discharge plug in line with the
closed throttle plate. The idle needle valve is
located in the air intake body, see Figure 3.
The 228 Series includes a two hole idle system
with one hole located above the closed throttle
plate and the other below the plate with the idle
needle valve located in the throttle body, see
Figure 3a,