Chevrolet 10 Series 1970 Service Manual page 304

BRAKES 5-66
1 Lock Ring
2 Spacer
3 Slack Adjuster
4 Camshaft Seal
5 Camshaft Bushing
Removal
1. R em ove a ir line and lamp socket.
2. Rem ove four instrum ent panel backing plate screw s
and rem ove backing plate fro m veh icle.
3. Separate gauge fro m backing plate by rem ovin g two
retaining screw s.
Testing Replacement Unit
The sim p lest way to test any dash p ressu re gauge is to
com pare it with a sp ecial test gauge that is known to be
accurate. By substituting one gauge fo r another at one
given point in the a ir brake system , this com parison can
be made.
Installation
1. Attach gauge to instrum ent panel backing plate using
o rig in a l s cre w s o r equivalent.
2. Mount backing p late-gau ge assem bly in instrument
panel.
3. R eplace lamp socket and gauge line.
4. Thoroughly check gauge connection fo r leakage.
Camshaft and Brake
6
Chamber Bracket
7 Backing Plate
Cam (integral with shaft)
8
9 Cam Roller
10 Brake Shoe
F ig . 108—Front W hee l Brake A ssem bly (W agner)
PRESSURE PROTECTION VALVE (Fig. 1 13)
A
guard against a ir p ressu re loss. It functions to close the
a ir lines to horns, w ipers, transm ission shift, d ifferen tia l
lock etc., when the pressu re in the main a ir system fa lls
below 65 psi.
Disassembly
1. Rem ove
2. Rem ove diaphragm, spring cap and spring.
Cleaning and Inspection
1. Wash a ll parts in cleaning fluid.
2. Inspect
Assembly
1. Position diaphragm, spring cap and spring on low er
2. A lign upper body with lo w er body, in stall four screw s
11 Brake Shoe Return Spring
12 Guide Pin Washer
13 Guide Pin "C " Washer
14 Guide Pin
15 Lock Ring
16 Anchor Pin
p ressu re protection valve is used in the system to
four screw s and separate the upper and
lo w er bodies.
diaphragm fo r cuts and punctures.
indentation of the diaphragm by the seat in the low er
body is norm al.
body.
and secure.
Some
CHEVROLET TRUCK SERVICE MANUAL