Chevrolet 70 Series 1970, Service Manual

Page: 349 / 841

BRAKES 5-58
1 Retaining Cage
2 " E a rs ” on W asher
3 R oller
4 Wedge R etainer
W asher
5 Wedge Return Spring
6 Return Spring W asher
7 C otter Pin
8 Wedge
Figure 31 —Wedge and Roller Assembly
Figure 32—Installing Seal on Anchor Plunger
be p rop erly u p set. Maximum braking efficien cy
can be obtained im m ediately if lin in gs a r e tru ed -
up w ith a lining grinder so they a re properly
cen tra lized in relation to cen ter of hub.
BRAKE SHOE INSTALLATION
(R efer to F ig . 30)
1. P o sitio n brake shoe w ebs in sid e hold-down
c lip s with ends engaging slo tted end o f anchor
p lu n gers and slo tted end of adjusting bolt.
NOTE: B rake sh o es a r e con stru cted with a
4 -in ch radius on the adjusting end and a 3-inch
radius on the anchor end. When in stallin g sh oes
on brake a sse m b ly , make certa in the end m arked
a s su g g ested in "NOTE” of Step 4 of "R em oval”
i s mounted in adjusting plunger.
2. In stall brake shoe return sp rin g s. Make
certa in hold-down clip applies p r e s s u r e to shoe
web to avoid cocked sh o e s.
BRAKE ACTUATION COMPONENTS
Actuation com ponents can be se r v ic e d without
rem oving sp id er from a x le. Trouble d iagnosis
might indicate faulty internal part o r p a rts which
would not n e c e ssita te brake cham ber d isa ssem b ly
or new brake lining. Actuation com ponents should
then be in sp ected for faulty or unacceptable con­
d ition s.
F or s e r v ic e of autom atic adjuster com ponents
s e e p roced u res under that subject on a p reviou s
page of th is sec tio n . The follow ing p roced u res
co v er the anchor end com ponents and other a c ­
tuation com ponents.
REMOVAL (R efer to F ig. 30)
1. R em ove drake cham bers. R efer to p ro ced ­
u r e s covering standard an d /o r " F a il-S a fe cham ­
ber s e r v ic e .
2. L oosen spanner nut, then u n screw non­
p r e s s u r e housing from brake sp id er. T his le a v e s
w edge, r o lle r and spring a ssem b ly exposed.
3. R em ove wedge, r o lle r and spring a ssem b ly
from actuation housing by pulling straigh t out.
4. R em ove brake sh o e s. R efer to procedure
coverin g th is operation.
5. R em ove plunger guides and w a sh ers.
6
. P ry plunger se a l from sp id er housing.
7. R em ove anchor plunger.
8
. R em ove autom atic adjuster com ponents as
d escrib ed in applicable p roced u res.
DISASSEMBLY OF WEDGE ASSEMBLY
(R efer to F ig s. 30 and 31)
1. R em ove co tter pin and wedge return spring
w ash er from wedge a ssem b ly .
2. Slide wedge spring off w edge.
3. R em ove wedge retain er w ash er and r o lle r s
fro m r o lle r retaining cage.
CHEVROLET SERIES 70-90 HEAVY DUTY TRUCK SHOP MANUAL