Chevrolet BEAUVILLE SPORTVAN G10 SERIES, Руководство по обслуживанию

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BRAKES 5-4
L IN IN G INSPECTION
Drum Brake
R eplace w henever th e thickness o f any p a rt o f any lining is
w orn to w ithin 1 /3 2 ” o f th e shoe table or rivet head whichever
is applicable.
A n o th er im p o rta n t p o in t to rem em ber, always replace
brake shoes in axle sets (rig h t and left side).
Disc Brakes
C heck b o th ends o f th e o u tb o a rd shoe by looking in at each
end o f the caliper. These are the points at w hich the highest
rate o f w ear norm ally occurs. H ow ever, a t th e same tim e,
check th e lining thickness on the in b o a rd shoe to m ake sure
th a t it has n o t w orn prem aturely.
R eplace w henever the thickness o f any p art o f any lining is
w orn to w ithin 1/32” o f the shoe or rivet whichever is
applicable.
H Y D R A U L IC BRAKE FLU ID
Use GM H ydraulic Brake F luid, Suprem e No. 11 or equiva­
len t w hen servicing brakes. This brake fluid is satisfactory for
any clim ate and has all the qualities necessary for proper
o peration, such as a high boiling p o in t to prevent vapor lock
and the ability to rem ain fluid at low tem peratures.
In the event th a t im proper fluid has entered th e system , it
will be necessary to service th e system as follows:
1. D rain the entire system .
2. T horoughly flush th e system w ith brake fluid.
3.
Replace all rubber parts o f the system, including brake
hoses.
4. Refill the system .
5. Bleed the system .
Flushing Brake Hydraulic System
I t is recom m ended th a t th e entire hydraulic system be th o r­
oughly flushed w ith clean brake fluid w henever new parts are
installed in the hydraulic system .
F lushing is also recom m ended if there is any d o u b t as to the
grade o f fluid in the system or if fluid has been used w hich
contains the slightest trace o f m ineral oil.
F lushing is perform ed at each w heel cylinder in tu rn , and in
th e same m anner as the bleeding o peration except th a t bleeder
valve is open ed
1
-
1 /2
tu rn s and the fluid is forced th rough the
pipes and w heel cylinder u n til it emerges clear in color.
A pproxim ately one qu art o f fluid is required to flush the
hydraulic system thoroughly.
When flushing is co m p leted a t all w heel cylinders, m ake
certain th e m aster cylinder reservoir is filled to p roper level.
Bleeding Hydraulic System
The hydraulic brake system m ust be bled w henever any line
has been disconnected o r air has in som e way en tered the
system . Bleeding o f brake system m ay be perform ed by one o f
tw o m e th o d s—eith er pressure or m anual.
Fig. 6 —B rake Bleeder J-2 3 5 1 8 and J -2 3 7 0 9 (T y p ic a l)
Sequence for Bleeding Wheel Cylinders
It is advisable to bleed one w heel cylinder at a tim e to avoid
allowing fluid level in reservoir to becom e dangerously low .
The correct sequence o f bleeding is to bleed wheel cylinder,
either fro n t or rear system , nearest m aster cylinder first. This
sequence expels air from lines an d w heel cylinders nearest the
m aster cylinder first and elim inates th e possibility th a t air in a
line close to the m aster cylinder m ay en ter a line farth er away
after it has been bled.
C A U T IO N : Do not perform bleeding operation
w hile any brake drum is removed.
PRESSURE BLEEDING (Figs. 6 and 7)
N O T E : Hydraulic brake pressure bleeding equip­
ment must be of the diaphragm typ e. That is, it
must have a rubber diaphragm between the air
supply and the brake fluid to prevent air, moisture,
oil and other contaminants from entering the
hydraulic system.
Fig. 7 —B leedin g Brakes w ith T o o l J-2 1 4 7 2
C H E V Y V A N S H O P M A N U A L