Chevrolet 70 1969 Series, Shop Manual

Page: 201 / 913

BRAKES 5A-8
1 Reservoir Cover
2 Master Cylinder Housing
Piston Return Spring
Primary Cup
Piston Assembly
Snap Ring
Boot
8 Check Valve (Brake Cylinder Only)
9 Check Valve Seat (Brake Cylinder Only)
10 Bleeder Valve (Brake Cylinder Only)
T -3 0 0 0
Figure 7— Double Barrel Master Cylinder Components
2. Connect hydraulic lines to brake and clutch
cylinder outlets.
3. Place push rod boots over ends of master
cylinder brackets.
4. Adjust push rods as directed under "Brake
Pedal and Linkage.”
5. Fill master cylinder reservoir and bleed
brake system as directed under "Bleeding Brakes."
MASTER CYLINDER OVERHAUL
The following procedures cover disassembly,
cleaning, inspection and repair, and assembly of
components used in both the brake and clutch cyl­
inder bores on double barrel master cylinders and
on brake cylinder bores on single barrel cylinders.
Disassembly (Fig. 7 )
Clean all dirt from outside of unit, using a
non-petroleum solvent.
2. Remove snap ring from groove in both cyl­
inder bores.
3. Remove piston assembly, primary cup,
return spring and retainer assembly, check valve
and check valve seat from brake cylinder bore
(single barrel cylinder does not have a check valve).
4. Remove piston assembly, primary cup, and
return spring and retainer assembly from clutch
cylinder bore.
5. Remove cover from cylinder housing.
6 . Remove bleeder screw (if necessary) on
double barrel cylinders.
Cleaning
Immerse all parts in denatured alcohol and
wash thoroughly. Wipe small parts dry and blow
out inside of reservoir and cylinder bores. Make
sure intake and bypass ports in cylinder housing
and bleeder holes in piston are clean.
C A U T IO N : Do not use kerosene or gasoline
for cleaning master cylinder components.
Inspection and Repair
Master cylinder repair kits are available
which contain all the parts ordinarily required
CHEVROLET SERIES 70 -80 H EAVY DUTY TRUCK S H O P M A N U A L