Chevrolet 70 1969 Series, Shop Manual

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T R A N SM ISS IO N S A N D CLUTCHES 7D-23
SECTION 70
CLUTCH CONTROLS
DESCRIPTION AND OPERATION
The clutch control system is typically and
schematically illustrated in figures 1, 2 and 3.
This system utilizes hydraulic pressure as a
means of transmitting clutch pedal movement to
the clutch release mechanism. The system con­
sists of a pedal-operated master cylinder and a
slave cylinder,
interconnected with hydraulic
lines. Clutch pedal is connected to the master
cylinder push rod, and the slave cylinder push rod
is connected to the clutch release fork or lever.
When clutch pedal is depressed, hydraulic
fluid is displaced from the master cylinder into
the slave cylinder, forcing the slave cylinder piston
outward. Movement of piston is transmitted through
slave cylinder push rod and clutch release fork or
lever, disengaging the clutch.
When pedal is released, return spring forces
pedal and cylinder pistons to normal (clutch en­
gaged) position. Fluid which was displaced into the
slave cylinder returns to the master cylinder, and
the clutch engages.
Master cylinders used on models covered in
Figure I — Clutch Hydraulic System (Typical
for Conventional Cab Models)
CHEVROLET SERIES 70-80 H EAVY DUTY TRUCK SH O P M A N U A L