Chevrolet BEAUVILLE SPORTVAN G10 SERIES, Руководство по обслуживанию

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BRAKES 5-2
Fig. 1 —M aster C y lin d e r—T y p ic a l
travel and th e n , w hen failed cham ber is b o tto m e d , the pedal
will harden.
I f a vehicle displays these sym ptom s, it is a good indication
th a t one o f the system s contains air or has failed, and it is
necessary to bleed or repair the brakes.
MASTER C Y L IN D E R
The m aster cylinder has tw o entirely separate reservoirs and
o utlets in a com m on b o d y casting. The fro n t reservoir and
o u tle t is con n ected to th e fro n t wheel brakes, and the rear
reservoir and o u tle t is con n ected to the rear wheel brakes. Tw o
pistons w ithin th e m aster cylinder receive m echanical pressure
from the brake pedal push rod and transm it it th rough the
brake lines as hydraulic pressure to the wheel cylinders. The
filler cap is accessible from inside the engine co m p artm en t.
V A L V E
All m odels have a com bination valve located below the
m aster cylinder. The fro n t and rear hydraulic lines are routed
through this com bination “ m etering” and “ brake failure w arn­
ing sw itch” to their appro p riate w heel cylinders or caliper.
The m etering p o rtio n o f the com bination valve tends to
“ hold o ff ” fro n t hydraulic pressure until the rear brake system
overcom es their pull back springs; th e n pressure is allowed to
flow w ith the result being a good d istribution o f braking
effo rt.
The brake failure w arning sw itch portio n o f the com bina­
tion valve “ senses” a loss o f hydraulic pressure, if a failure
should occur, and illum inates a red light in the dash to warn
the operato r o f th e failure.
DISC BRAKES FR O N T—(Fig. 4)
All m odels have disc brakes on the fro n t. The one piece
caliper m ounts on the steering knuckle/steering arm , which is
also a one piece casting, an d astride the brake disc. The caliper
is the single piston design w hich is said to be a sliding caliper
sliding piston. No front brake adjustm ent is necessary once the
system is in operation and the pedal has been stroked to
“ seat” the shoes to the caliper.
DRUM BRAKES REAR—(Fig. 5)
The rear brakes are duo servo w hich are self adjusting.
Brake adjustm ent takes place w hen the brakes are applied w ith
a firm pedal effort while the vehicle is backing up. A pplying
the brakes moves the ac tu a to r w hich turns the star wheel and
lengthens the adjuster screw assem bly. This action moves the
shoes outw ard until clearance betw een the lining and drum is
w ithin p ro p er lim its.
G A S K E T
M O U N T I N G B R A C K E T
S TO P L A M P S W IT C H
STRIKER
C LE V IS
B RAKE A N D C L U T C H
P E D A L B R A C KE T
L O C K N U T
P U SH R O D
B RAKE PED A L
B U M P E R
Fig. 2 —Master C ylinder M ounting
C H E V Y V A N S H O P M A N U A L