-
Spring Installation
not between the guide and the
shoe web. Be certain that the cable
eye is not cocked or binding on
the anchor pin when installed.
All
parts should be flat on the anchor
pin.
Remove the brake cylinder
clamp.
7.
Apply high-temperature grease
(Stanalube Poly) to the threads and
the socket end of the adjusting screw.
Turn the adjusting screw into the
adjusting pivot nut to the limit of
the threads and then back off
Yz
turn.
Interchanging the brake shoe ad-
justing screw assemblies from one
side of the car to the other would
cause the brake shoes to retract
rather than expand each time the
automatic adjusting mechanism
operated.
To prevent accidental in-
stallation of the adjusting screw on
the wrong side of the car the socket
end of the adjusting .screw is stamp-
ed with an R or
L
(Fig. 10). The
adjusting pivot nuts can be distin-
guished by the number of grooves
machined around the body of the
nut. Two grooves indicate a right-
hand nut; one groove indicates a left-
hand nut.
8.
Place the adjusting socket on the
screw and install this assembly be-
tween the shoe ends with the ad-
justing screw toothed wheel nearest
the secondary shoe.
ADJUSTING LEVER
ADJUSTING
SCREW
IDENTIFICATION LINES
HI
143-A
FIG.
10-Adjusting
Screw and Lever Identification
9.
Hook the cable hook into the
hole in the adjusting lever. The ad-
justing levers are stamped with an
R or
L
to indicate their installation
on a right- or left-hand brake as-
sembly (Fig. 10).
10.
Position the hooked end of
the adjuster spring completely into
the large hole in the primary shoe
web. The last coil of the spring
should be at the edge of the hole.
Connect the loop end of the spring
to the adjuster lever hole (Fig.
1).
11.
Pull the adjuster lever, cable
and automatic adjuster spring down
and toward the rear to engage the
pivot hook in the large hole in the
secondary shoe web.
12.
After installation, check the
action of the adjuster by pulling the
section of the cable between the
cable guide and the adjusting lever
toward the secondary shoe web far
enough to lift the lever past a tooth
on the adjusting screw wheel. The
lever should snap into position be-
hind the next tooth, and release of
the cable should cause the adjuster
spring to return the lever to its
original position. This return action
of the lever will turn the adjusting
screw one tooth.
If pulling the cable does not pro-
duce the action described, or if the
lever action is sluggish instead of
positive and sharp, check the position
of the lever on the adjusting screw
toothed wheel. With the brake in a
vertical position (anchor at the top),
the lever should contact the adjust-
ing wheel KO inch
(plus or minus
%z
inch) above the centerline of the
screw. If the contact point is below
this centerline, the lever will not lock
on the teetn in the adjusting screw
wheel, and the screw will not be
turned as the lever is actuated by
the cable.
To determine the cause of this
condition:
a.
Check the cable end fittings.
The cable should completely fill or
extend slightly beyond the crimped
section of the fittings. If it does not
meet this specification, possible
darn-
age is indicated and the cable as-
sembly should be replaced.
b.
Check the cable length. The
cable should measure
8%0 inches on
6-cylinder models or 10% inches
on 8-cylinder models from the end
of the cable anchor to the end of
the cable hook.
c.
Check the cable guide for dam-
age. The cable groove should be
parallel to the shoe web, and the
body of the guide should lie flat
against the web. Replace the guide
if it shows damage.
d.
Check the pivot hook on the
lever. The hook surfaces should be
square with the body of the lever
for proper pivoting. Replace the
lever
if the hook shows damage.
e.
See that the adjusting screw
socket is properly seated in the notch
in the shoe web.
WHEEL CYLINDER REPAIR
It is not necessary to remove the
brake cylinder from the backing
plate to disassemble, inspect, or hone
and overhaul it. Removal is necessary
only when the cylinder is damaged
or scored beyond repair.
DISASSEMBLY
1.
Remove the links and the rub-
ber boots from the ends of the brake
cylinder. The 6-cylinder models are
not provided with links. Remove
the pistons, cups, and return spring
from the cylinder bore (Fig.
1 1
)
.
2.
Remove the bleeder screw from
the cylinder.
INSPECTION
1.
Wash all parts in clean de-
natured alcohol. If alcohol is not
available, use specified brake fluid.
Dry with compressed air.
2.
Check all internal parts for ex-
cessive wear or damage.
If any of
the internal parts require replac-
ing,
a11 should be replaced.
3.
Inspect the cylinder bore for
score marks or rust. If either con-
dition is present, the cylinder bore
must be honed.
However, the cyl-
inder should not be honed more
than
0.003
inch beyond its original
diameter.
A baffle in the front wheel
cylinder of the 6-cylinder models
prevents honing, therefore, they must
be replaced.
4.
Check the bleeder hole to be
sure that it is open.
ASSEMBLY
1.
Apply a coating of heavy-duty
brake fluid to all internal parts.
2.
Thread the bleeder screw into
the cylinder and tighten securely.
3.
Insert the return spring, cups,
and pistons into their respective posi-
tions in the cylinder bore (Fig.
11).
Place a boot over each end of the
cylinder.
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