Early Fuel Evaporation ( EFE ): Description and Operation

Fig. 30 - EFE Installation Typical:

PURPOSE
Provides a source of rapid heat for quick induction system warm-up during cold engine operation--providing better fuel evaporation and a more uniform mixture

OPERATION
The vacuum operated EFE heat control valve mounted between the exhaust manifold and pipe--Fig 30--directs a portion of the exhaust gases through the intake manifold to the base of the carburetor during engine warm-up.

Thermal Vacuum Switch (TVS) - Regulates EFE valve temperature at or below the temperature shown;

6 Cyl 150° F
V8 180° F

- When engine coolant is at or below the specified temperature, the TVS will cause vacuum to flow to the EFE control valve--actuator assembly, diverting the exhaust gases through the intake manifold to the base of the carburetor.

- At temperatures above those specified, the TVS closes off vacuum to the EFE control valve stopping the flow of exhaust gases through the intake manifold.

Actuator Assembly - Attached to the exhaust manifold--Fig 30. Remotely located actuators are secured by a bracket, and connected to the heat control valve by a rod.