Chevrolet 30 Series 1967 Service Manual page 244

BRAKES 5-28
WHEEL CYLINDERS
Removal (Fig. 53)
Duo-Servo Type
1. Jack up axle and remove wheel, brake drum and
brake shoes a s directed u n d e r
Removal."
2. At front, disconnect metal brake tube from flexible
hose at frame, disconnect hose from frame, then un­
screw hose fitting from wheel cylinder connector, or
from wheel cylinder housing where connector is not
used. At rear, disconnect metal brake tube from
wheel cylinder connector.
Remove cap screws and washers attaching wheel
3.
cylinder to flange plate and remove cylinder assem ­
bly. Remove connector, i f used, f r o m cylinder
housing.
Tw inplex Type
1. Jack up axle and remove brake shoes as directed
under Brake Shoe Removal.
2. Disconnect brake tube from rear wheel cylinder
connector at inner side of flange plate. Remove
brake tube connecting wheel cylinders at outer side
of flange plate. Remove dust shield from upper end
of each cylinder.
Remove cap screws and lock washers attaching wheel
3.
cylinders to flange plate, then remove wheel cylin­
ders and heat shield. Remove brake line connectors
from cylinder housings.
Type " F " (Fig. 54)
1. Jack up axle and remove brake shoes as directed
under " Brake Shoe Removal."
2. Disconnect axle brake tube from inlet connector at
upper cylinder. Remove inlet connector attaching
connecting tube fitting to upper cylinder, and remove
DUO-SERVO
TWINPLEX
---------
5 3 —Duo Servo and Tw inplex C ylinders
Fig.
" Brake Shoe
Fig.
bolt attaching connecting tube fitting to lower cylin­
der. Remove connecting tube and fittings assembly.
Remove one large and two small cap screws attach­
3.
ing each cylinder to flange plate, then remove cylin­
ders from backing plate.
Type " FR-3"
1. Jack up axle and remove brake shoes as directed
under " Brake Shoe Removal."
2. Remove bolts attaching brake line connectors to
wheel cylinders at inner side of flange plate.
Remove two cap screws and lock washers attaching
3.
each wheel cylinder to flange plate. Remove wheel
cylinders and heat shields, then remove heat shields
from cylinders.
Disassembly
Type " F "
Pull boot off end of cylinder, then remove boot and
piston. Pull boot off piston. Brake shoe guide is pressed
into piston and cannot be removed. Remove piston cup,
cup filler, and spring from cylinder. Remove bleeder
valve from cylinder.
A ll Types Except Type " F "
Pull boots off ends of cylinders and remove push rods
from boots. Push pistons, cups and spring out of cyl­
inder. Duo-Servo and Twinplex type wheel cylinders are
equipped with spring assemblies consisting of a spring
between two lip expanders, as shown in Figure
Inspection
Repair kits are available which contain the parts to be
replaced when overhauling wheel cylinders.
1. Inspect cylinder bore for scores, scratches, or
corrosion.
TYPE "F"
TYPE "FR-3"
54—
W h eel Cylinders Used w ith Types " F " and
" FR-3" Brakes
Light scratches or slightly corroded
53.
CHEVROLET TRUCK SERVICE MANUAL