Governor Assembly; Solenoid And Valve Assembly - Jeep 1979 CJ-5 Technical & Service Manual

1H-Z CRUISE COMMAND
Bellows
The bellows, a vacuum servo, receives the modulated
vacuum and controls the vehicle speed by actuating the
throttle through a beaded chain.
Control Switch
The control switch is an integral part of the turn
signal lever. When actuated, it energizes either the sole-
noid valve, the coupling coil or both.
Release Circuit
When the brake pedal is depressed slightly, the stop-
lamp current de-energizes the solenoid valve, dis-
engaging the speed control.
OPERATION
General,
The regulator consists of three functional groups: the
governor assembly, the solenoid and valve assembly,
and the coupling coil and centering spring assembly.
Governor Assembly
The governor assembly consists of two flyweights on a
shaft, an actuator assembly, and a spring (fig. 1H-1).
The shaft passes through the actuator assembly but is
not keyed to it. The actuator is free to slide on the shaft.
The spring applies pressure which holds the actuator
against the flyweights. When the shaft is spun by the
speedometer cable, the flyweights are thrown outward
by centrifugal force. This forces the actuator to slide
away from the flyweights against the resistance of the
spring. At a road speed of approximately 30 mph, the
actuator has moved far enough to close the low speed
switch. A spring-loaded slider on the actuator engages a
drive pin on the coupling coil.
Solenoid and Valve Assembly
The valve controls vacuum entering the regulator by
sealing the manifold vacuum port until the solenoid coil
is energized (fig. 1H-2). When current is supplied to the
coil, the valve stem is pulled upward, opening the mani-
fold vacuum port. When the coil is de-energized, the
valve is pushed shut by the spring.
A glass-encapsuled reed switch is mounted on the
outside of the solenoid coil. The magnetic field surround-
ing the energized coil activates the reed switch and per-
mits current to pass. As long as current is supplied to
the reed switch, the coil remains energized, holding the
valve open.
7 0 0 6 7
Fig. 1H-1
Governor Assembly
7 0 0 6 8
Fig. 1H-2 Solenoid and Valve Assembly