Carburetor: Description and Operation: 2150

Fig. 1 Motorcraft model 2150 2 barrel carburetor less altitude compensator, exploded view:

Carburetor:

The Air Horn
Serves as a cover for the throttle body, contains the choke plate and vents for the fuel bowl.
- V-6 engines The air horn assembly contains a fuel deceleration system which consists of a metered pickup orifice in the fuel bowl and air/fuel mixing orifices and bleeds.

The Throttle Body
- The throttle plate, accelerating pump, power (enrichment) valve and fuel bowl are housed in the throttle body.
- The choke housing is attached to the throttle body.

The two bodies each contain a main and booster venturi, main fuel discharge, accelerating pump discharge, idle fuel discharge, and a throttle plate.

Automatic Transmission - Anti-Stall Dashpot
On some units, an anti-stall dashpot is attached to the carburetor when the vehicle is equipped with an automatic transmission.

Altitude Compensation
Some units are equipped with an altitude compensation aneroid to improve high altitude emission control and driveability.
- Intake air entering the bypass valve is metered into the air flow above the throttle plates, leaning the mixture for high altitude operation.
- Air flow is controlled by a valve activated by an aneroid attached to the rear of the carburetor main body.
- These units are also equipped with a choke in the bypass air intake, linked to the main choke.

Choke System
An electric choke system is incorporated which opens choke plate within 1 - 1-1/2 minutes when under hood temperatures are above approximately 55° to 60°. The electric choke system is supplied current to open the choke when under hood temperatures are between 54 and 74° F.

Feedback Controlled Models Only
The air horn assembly has an auxiliary fresh air intake for the duty cycle solenoid/altitude compensator.

The main body has a provision at the back to attach the duty cycle solenoid/altitude compensator as well as an opening that accepts auxiliary fresh air from the horn and channels that link up to the bleed circuits to the booster support assembly.

There is also a throttle angle potentiometer (Throttle Position Sensor) mounted on the throttle at the choke side.

The booster support assembly has cast in channels that flow bleed air to the idle and main system vacuum circuit.