2100 Vs. 2150 Motorcraftby John Stevens J.D.
The Motorcraft division of Ford Motor Co. manufactured both the 2100 and 2150 two-barrel carburetors. The 2100 carburetor was used during the 1960s, whereas the 2150 model was most notably used during the 1970s. Both models are relatively easy to locate today, as the company fitted both devices onto base-model six- and eight-cylinder engines. Both models featured the same basic design, but the 2150 model was essentially a 2100 that included emissions-reducing equipment. For this reason, the 2100 may be a more appropriate carburetor for creating power and the 2150 may be a better choice where mileage and emissions are important.
Both the 2100 and the 2150 models consist of two main components: the throttle body and the air horn. The air horn is the upper portion of the carburetor, and acts as a lid over the throttle body. Within the air horn lies a choke plate and the fuel bowl vents. Within the throttle body can be found the fuel bowl, the throttle plate, the accelerating pump and a single power valve.
Unlike the 2100, the 2150 model contained a staged choke system for the 1972 production year. The system employs a bimetal sensor that is used in conjunction with a series of diaphragms to open the choke plate. The system operated only when the temperature underneath the hood exceeded approximately 60 degrees. Beginning with the 1973 production year, the 2150 featured an electric choke system that replaced the staged system. The purpose of the electric system was the same as with the staged system, but this system opened the choke plates when the under-hood temperature exceeded approximately 55 degrees.
Some models of the 2100 carburetor were equipped with an anti-stall dashpot. Those 2100s that featured a dashpot were fitted only onto engines mounted to an automatic transmission. By contrast, the 2150 carburetor did not contain an anti-stall dashpot. The purpose of the dashpot was to reduce the speed at which the throttle valves closed when the driver released the accelerator pedal. Locating the dashpot is perhaps the quickest way to distinguish a 2100 carburetor from a 2150. The dashpot is a saucer-shaped component mounted in front of the throttle linkage on the driver's side of the carburetor.
Fuel Deceleration System
Ford included a fuel deceleration system within those 2150 carburetors fitted onto six-cylinder engines. The 2100 carburetor was never equipped with a fuel deceleration system. The system was contained entirely within the air horn assembly and consisted of a metered pickup orifice within the fuel bowl and a number of air and mixing orifices and bleeds. The system reduced emissions and improved fuel efficiency by preventing gasoline from flowing through the carburetor's idle circuit upon deceleration.