1933-34 Zenith Carburetor ?

[Ron in Quincy]

I recently acquired a 33-34 Zenith carburetor lower housing. In the 40 plus years of working on carburetors I have never seen a lower housing like this.

Could someone please identify what the application might be ? With out the upper housing, which must also be different, I can not figure how it would work.

The choke lever and plate was in the housing; when in a closed position it covers the passageway; it has a spring loaded valve on the plate; there is no provision for attaching a lever to the threaded end of the shaft so there must be some special arrangement from the upper housing?

It is set up for the standard high speed jet and idle jet like a regular C carburetor (33-34).

I am attaching pictures and would appreciate any feed back.

Ron

 

[Ron in Quincy]

btt

 

[Bob C]

My guess is the passage is a balance tube that would go to the
float bowl when the carb is used with an air cleaner.

Bob

 

[darrylkmc]

Ron in Quincy,

Since it has no GAV, it was never used for car or truck production. I have a couple carbs similar to the one shown, I do not know what the service is, the Venturi's on both of my examples is a 17.

Darryl in a Very Warm and dry Fairbanks

 

[ursus]

This carb was made after the Model B era for some kind of industrial application. The lack of a GAV, the choke feature and, as I have seen on similar versions, the use of a narrowed venturi points to a low RPM industrial use.

 

[Ron in Quincy]

Darryl,

Do you have a upper housing that has the same bottom housing as mine ?

The reason I am asking is the fact that the pick up tube that is pressed into the upper housing would have to angle as the passage way on mine angles toward the back where a regular carb housing the pick up tube is vertical to the upper housing.

I sure wish this carb had been complete then I could figure out how it functions.

This housing takes a regular B venture, main jet, and idle jet just like the car version.

The only time this passageway would function is when the choke plate is in a closed position, the minute it is opened to horizontal there would be no draw on the passageway.

Do you have any thought as to what kind of commercial unit it may have been on ?

Ron

 

[Tom Wesenberg]

That is a balance tube (passage) on the carb and would function to balance the air pressure behind the air filter and over the fuel bowl.

 

[darrylkmc]

Ron,

I will look through my carbs and post photos of the upper and lower castings, it may be a day or to before I can post them.

Darryl in Fairbanks

 

[FL&WVMIKE]

RON IN QUINCY ...........................
I have this complete ZENITH carburetor, that I don't know what it fits either. I hope that someone can solve our puzzles.
I believe that mine is NOS, as I found it in an old parts store, years ago.
Thank you,
MIKE (mikeburch)

 

[Bob C]

This one has the same 7757 number but looks totally different.

Bob

 

[Dodge]

I would say that's a universal replacement carb of the era

 

[Ron in Quincy]

Mike,

Thanks for the pictures of the complete carburetor.

It is no doubt that it is for commercial application.

Like you, maybe someone will have acquired a unit that had this type carburetor on it, then we will have a better idea how it was used.

Ron

 

[Tom Wesenberg]

Does "commercial" include fram tractor?

 

[Ron in Quincy]

Tom W.,

Sure does, as a matter of fact I was thinking a tractor would be a good candidate, especially after the pictures posted with the special throttle controls, etc.

Ron

 

[myjunk]

Hi Guys, I am new to the forum. I have a Zenith carburetor also that I have no clue what it went with. Even though it is similiar to the ones used on the model , I know it isnt. I welcome your thoughts. Thanks

 

[Mike V. Florida]

Based on the near infinite adjustments, and the cable clamp I feel it is a "universal" commercial carb for things like forklifts. Like the one used on Model A's, 14544