Zenith Carb markings
 

I bought a 1929 Coups about a month ago. It has a lot of the original parts on it. Looking at the zenith carb the upper body it is marked with an "Z" but the bottom half has no markings. All of the Zeniths I have had over the years always had Zenith 1, 2 or 3 marked on the lower half. It uses all Zenith parts and otherwise looks like a Zenith 1 and 2. Any ideas why the lower half is not marked?

Re: Zenith Carb markings
 

not marked lower half bodies were produced by Holley Jul- Dec 1928 ( from Steve Pargeter's excellent Zenith Model A Guidelines Restoration Guide) . FYI they are all interchangeable.

Re: Zenith Carb markings
 

https://i.imgur.com/GualLVR.jpg?1

Some were marked with a raised "H" on the lower bowl.What I've read (and please correct me if I'm wrong) is that Ford and George Holley didn't see eye to eye but allowed Holley to build under contract till Zenith could get their capacity up to Ford demand.

Re: Zenith Carb markings
 

Also, in order to return defective carbs from the dealers to holly a marking system evolved.

Re: Zenith Carb markings
 

I didn't know that Bob, what marking did they put on them?

Re: Zenith Carb markings
 

The mismash we find trying to id the castings.
I'm still trying to learn it.

Re: Zenith Carb markings
 

Here are a couple more that can stir the pot as to when, where and who. The upper one, plain raised Zenith is not the Early style Carb, it has the screw in secondary well as does the lower one..

Re: Zenith Carb markings
 

... Good game this! Actually the early carbs are the ones with the brass GAV seat... 1930 and after they went to integral in casting . So... from lettering and seat I would date the upper a Zenith 1927 to early 1929. The lower a Holley , Jan '29 to sometime in 1930 .
LaterrArrgh sorry I was mixing my GAV seats and secondary wells ( a painful experience) - Worra load of tosh I've written!-- I plead it's an age thing.

Re: Zenith Carb markings
 

Steve Schmach also did some excelent articles about carburetors in the following The Restorer's (MAFCA):

“A Guide to Zenith Carburetors…Part 1…The 1927 Zenith Carburetors”: TR/61/6/8 (2017)
“A Guide to Zenith Carburetors…Part 2…The 1928 Zenith Carburetors”: TR/62/1/8-9 (2017)
“A Guide to Zenith Carburetors…Part 3…The 1929 Zenith Carburetors”: TR/62/2/8-11 (2017)
“A Guide to Zenith Carburetors…Part 4…The 1930 Zenith Carburetors”: TR/62/3/8-11 (2017)
“A Guide to Zenith Carburetors…Part 5…The 1931 Zenith Carburetors”: TR/62/4/8- 14 (2017)


Pluck

Re: Zenith Carb markings
 

For those of us that do not know the "new Math" what does this mean?


TR/61/6/8 (2017)
TR/62/1/8-9 (2017)
TR/62/2/8-11 (2017)
TR/62/3/8-11 (2017)
TR/62/4/8- 14 (2017)


Thanks

Re: Zenith Carb markings
 

My Holley has the capital H on the lower half and also just above it an H on the upper half. Is that common or does it denote a certain production period of time?

Re: Zenith Carb markings
 

"H over H" is Holley (with upper "H" directly above lower "H").


July 28 though Sept 28

Re: Zenith Carb markings
 

Great question...The Restorer TR/Vol. 61/No. 6/Page 8 (Year 2017)

Pluck

Re: Zenith Carb markings
 

Holley Top; 1928 Jan.-June-- H
Bottom; 1928 Jan.--June--H (No Secondary Well for Brass insert, Cast Only)

Holley top; 1928 July-Aug.--1931 Plain.
Holley Bottom; 1928 Plain Has Secondary Well for brass Brass insert.

Re: Zenith Carb markings
 

Rich, Yours was made and used from Jan. 1928 thru June 1928. It is of the Double Venturi style.. No secondary Brass Well, just the cast hole, not threaded.

Re: Zenith Carb markings
 

In the 70's I had a zenith 1,2,3 that was all marked. they say there was also one with no number on it.

Re: Zenith Carb markings
 

Many people do not understand the designators on the Zenith carbs. They were all "Zenith" design but not necessarily made by Zenith.


The "Zenith" body with Zenith and no numbers was made by Zenith from 1927 - June 1929.


The "Zenith" body with Zenith-1 were made by Zenith from July 1929 to the end of production.


The "Zenith" body with a H were made by Holley from Jan-Jun 28.


The "Zenith" body with no marking were made by Holley from Jul-Dec 28.


The "Zenith" body with Zenith-2 were made by Holley from Jan 1929 to the end of production.


The "Zenith" body with Zenith-3 were made by Ford from 1931 to the end of production.