Chevrolet 10 Series 1970 Service Manual page 311

1. End Cap
2. Seal
3. N u t
4.
V a lv e Disc
5. V a lv e Body
6. V a lv e Return S pring
11. In stall c o v e r and name plate and secu re with pan
head screw .
Installation
1. If a new va lve assem bly is being installed, in stall
operating le v e r and shaft which w ere rem oved fro m
old unit. A lso , in sta ll a ir line connector fittin gs in
in let and outlet p orts, using sealing compound on
connector threads. Keep sealin g compound o ff fir s t
two threads of fitting.
To Stop
Light Switch
Valve Guide
Body
Brake
Application
Valve
Delivery Port
To Trailer Brake
Service Line
F ig . 123— D oub le C heck V a lv e
Fig. 122—A irb ra k e Hand C o ntrol V a lv e
7. V a lv e S pring R etainer
8. Piston Return S pring
9. Piston Cup
10. Piston
11. S pring
12. Cam
Gasket
Shuttle Valve
Cover
From Trailer
Brake Hand
Control Valve
13. Cam S haft
14. Cam Housing
15. A d ju s tin g Bearing
16. C o lla r
17. C over
2. P osition va lve and secure with two bolts and lock
washers. Tighten bolts firm ly .
3. Connect a ir lin es to va lve.
4. Build up a ir p re ss u re in system and test va lve op ­
eration as p reviou sly directed.
DOUBLE CHECK VALVE (Fig. 1 23 )
A combination double check va lve and stop ligh t switch
is used in the brake system with tr a ile r brake con trols.
The va lve is used to connect both the foot brake app lica­
tion va lve and the tr a ile r brake hand control va lve.
Disassembly
Rem ove two cap screw s and lock w ashers attaching
va lve c o v e r to body. R em ove co ve r and gasket, then r e ­
m ove shuttle va lve and va lve guide.
Installation
Wash a ll p a rts in a cleaning solution and wipe dry.
Examine a ll parts fo r co rro s io n o r deterio ra tio n and r e ­
p lace as n ecessa ry. Make sure shuttle va lve w ill slid e
fr e e ly back and forth in va lve guide.
Assembly
Apply a thin coating o f Lubriplate o r equivalent to in ­
side o f va lve guide. P la c e va lve guide and shuttle va lve
in body. P osition c o v e r on body, using new gasket. In ­
s ta ll c o v e r cap sc rew s and lock w ashers, and tighten
even ly and fir m ly .
FRONT BRAKE LIM ITIN G VALVE A N D
T W O -W A Y CONTROL VALVE (Figs. 124 and 1 2 5 )
A combination limiting and quick release valve and a
BRAKES 5-73
18. N u t
19. O p e ra tin g Lever
20. N am e P late
21. Lock W asher
22. Screw
CHEVROLET TRUCK SERVICE MANUAL