zenith 62-162-63-263 Tech

General Characteristics

The Zenith model 62 and 63 series are a family of cast iron updraft carburetors produced from the 1930s to the 1980s. They were used in a vast number of industrial, marine and truck applications. The overall design consists of two main iron castings, the float bowl and throttle body (upper part with the throttle shaft). There is a venturi insert cast of zinc in the throttle body. The float is a dual pontoon type, and there three different ones for the different size groups of these carbs.

The main difference between the two models is that the model 63 has an accelerator pump but the 62 does not.

Identification

Typical carburetors

Model 62 size 9-10	Model 62 size 12	Model 63 size 9-10	Model 63 size 11-12	Zenith model 63 size 14-16

Model 62 carbs were produced in two size groups which used the same float bowl dimensions, but had different throttle bores. These were size 9 and 10, and size 12. Size 9 and 10 carburetors have four screws holding the two halves of the carburetor together. Size 12 carbs use 6 screws.

Model 63 carbs were made in three size groups, size 9-10, size 11-12 and size 14-16. The three groups use different castings. Size 9-10 has four screws holding the two halves together, size 11-12 and 14-16 use six screws.

Zenith carburetors have a round disc the size of a dime on the top of the float bowl stamped with the carburetor numbers. Please refer to our article on how to find Zenith carburetor numbers.