Chevrolet 10 Series 1970, Руководство по обслуживанию

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BRAKES 5-69
SERVICE RECOMMENDATIONS
FO OT H O U S IN G
HSG. LOCK G R O O V E
PISTON
“ O ” RING
t
PISTON
SEAL
SET SNAP RING
SCREW HEX N U T -
SQUARE NUT
BACK-UP
RINGS
O ” R IN G
BACK-UP R IN G
(P O S ITIO NE D IN
PISTON G R O O V E )
POW ER SPRING
CAP
LOCK R IN G (PO SITIO NED
OVER CAP LIP A N D IN
H SG. LOCK G R O O V E )
“ E” R IN G
RELEASE
BOLT
BEARING WASHER
RUBBER SEAL
INNER
WASHER
OUTER
— W ASHER
" O ” R IN G
F ig . 117—Super F a il Safe E xplode P osition
Caging and Uncaging Pow er Spring
On the Super F a il-S a fe the head o f the re le a s e bolt
is exposed at a ll tim es.
The p ow er spring is caged by rotating the re le a s e
bolt 18 to 21 fu ll turns clock w ise. Do not fo r c e the
bolt beyond its norm al stop.
Both the caging and uncaging operation can be made
e a s ie r by applying a ir p ressu re (65 psi minimum) to the
F a il-S a fe . This w ill take the spring load o ff the re le a s e
bolt.
DISASSEMBLY OF SUPER FAIL-SAFE (Fig. 1 17 )
NOTE:
It w ill be n ecessa ry to hold the pow er
sprin g in com p ression fo r d isassem bly. A f ix ­
ture as illu stra ted in fig . 119 can be fabricated
fo r this operation.
1. Cage pow er spring by turning r e le a s e bolt 18 to 21
turns clock w ise.
2. R em ove F a il-S a fe fro m non-pressu re housing at
clam p ring.
3. R elea se foot set screw .
4. U nscrew foot fro m piston.
5. R em ove piston seal.
6. R em ove sealin g compound located at joint between
cap and housing.
7. R em ove lock ring fro m housing.
8. Separate cap, spring and piston assem bly fro m
housing.
9. Rem ove back-up rin gs and “ O ” ring fro m gro o ve
in housing.
10. R em ove hex nut and snap ring fro m re le a s e bolt.
11. Secure cap, spring and piston assem bly in fixtu re.
12. Turn re le a s e bolt until square nut fa lls fr e e .
13. R elease p re s s u re on fixtu re until spring is unloaded.
14. R em ove assem bly fro m p ress o r fixtu re.
15. Separate cap fro m spring and piston assem bly.
16. Rem ove back-up ring and “ O ” ring fro m piston.
17. Rem ove the two spring bearing w ashers.
18. Rem ove c o tter pin o r snap ring fro m re le a s e bolt.
19. R em ove fla t w asher fro m re lea se bolt.
20. Rem ove re le a s e bolt fro m cap.
21. Rem ove “ O ” ring fro m re le a s e bolt.
22. R em ove second fla t w asher fro m re le a s e bolt.
23. Do not rem ove b rea th er assem bly fro m cap.
ASSEMBLY OF SUPER FAIL-SAFE
B e fo re assem bly, clean and inspect a ll parts. L u b ri­
cate with recom m ended grea se. Do not lu bricate cap in
the a rea o f the b rea th er assem bly. Do not use solvent
on back-up o r “ O ” rin gs. Use hot soapy w ater and wipe
clean.
It is n ecessary to use a s e a le r on the foot set screw
and c o v e r the head o f it with plastic tape until the s e a le r
sets.
CHEVROLET TRUCK SERVICE MANUAL