Rebuild Procedures (Zentih 61/161)
Exploded View and Diagrams (Zenith 61/161)
Printable Service Instructions
Fuel Supply System (Zenith 61/161)
High Speed System (Zenith 61/161)
Economizer System (Zenith 61/161)
The 61 and 161-series carburetors are of the single barrel, single venturi updraft design with a semi-concentric fuel bowl to allow operation at quite extreme angles without flooding or starving. They are of the “balanced” or “sealed” type, in that all air for idle and high speed operation as well as for fuel bowl ventilation must enter through the air cleaner. Some models are available with or without main jet adjustment and back suction economizer. The fuel supply system is made up of the threaded fuel inlet, fuel valve (needle and seat), floats and fuel bowl. The idle system is made up of the idle discharge port, idle air passage, idle adjusting needle, idle jet and fuel passage. The high speed system consists of the venturi, main jet, well vent, and main discharge jet. The economizer system consists of a “milled” slot in the throttle shaft (which acts as a valve), a vacuum passage between the throttle bore and slot in the throttle shaft, and a vacuum passage from the slot in the throttle shaft to the fuel bowl. The choke system is of the semi-automatic type and includes a choke palte with built-in poppet valve, choke shaft and external choke lever.
Type: Updraft
Material: Barrel and bowl gaskets, cast iron
| SIZE | NORMAL SIZE | THROTTLE BORE DIAMETER | FLANGE SIZE S.A.E. STANDARD |
|---|---|---|---|
| 5 | 5/8” | .787 or 25/32” | 5/8” |
| 7 | 7/8” | 1.023 or 1 1/32” | 7/8” |
| X7 | 7/8” | 1.023 or 1 1/32” | 1” |
| XX7 | 7/8” | 1.023” or 1 1/32” | 1 1/4” |
| 8 | 1” | 1.181 or 1 3/16” | 1” |