Chevrolet 30 Series 1967 Service Manual page 227

F ig . 22—P I 0-20-30 Parking Brake Front C ab le Adjustment
3. Back off nuts and " F " (fig. 24). Back off nut
" E "
" D" and adjusting nut on bolt " C" .
NOTE:
Do not remove nuts, loosen only.
4. Remove lock wire from anchor screw " B " .
5. Adjust anchor screw " B " until there is .010 to .015
clearance between lining and drum at anchor screw.
. Tighten adjusting bolt " C" until there is .020 clear­
6
ance between drum and lower end of brake band.
7. Tighten lock nut " D" .
. Tighten up adjusting nut " E " until there is .020
8
clearance between drum and upper end of brake band.
9. Tighten up lock nut " F " .
10. Adjust brake pull rod so the clevis pin can be in­
stalled in the cams while the brake cam rests flat on
the upper brake band bracket.
11. Install cotter pin in clevis pin of brake pull rod and
tighten lock nut on pull rod.
12. Install lock wire on anchor screw " B " .
13. Recheck all points of facing for correct clearances.
T Models (Figs. 23 and 26)
Tilt Cab vehicles are equipped with a compound type
lever that applies the transmission mounted parking
brake by means of a flexible cable. The lever incor­
porates a cable adjustment feature that allows the oper­
ator to adjust the "ov er-cen ter" position required to lock
the parking brake in the applied position.
Adjustment
1. Turn adjusting knob of lever asm. counterclockwise
to bottom position. Attach brake cable to Orscheln
brake lever asm. With the lever in the "brake off"
position, adjust brakes for proper clearance and
remove slack from brake cables by adjusting clevis
at transmission.
2. Test the brakes by pulling to the "brake on"
position. A definite snap-over-center should be felt.
Turn the adjusting knob in a clockwise direction until
a snap-over-center is felt.
3. Oil all moving parts.
Propeller Shaft Parking Brake—Single Shoe Type
(Fig. 25)
1. Set hand brake lever in the fully release notch of the
ratchet sector.
2. Loosen lock nut " D" and draw up adjusting bolt
" A" to secure clearance between outer shoe facing
and brake drum of .010"-.015" measured at a point
directly above bolt " A" . Then hold bolt and tighten
lock nut securely.
3. Loosen lock nut " C" and draw up nut " B " to secure
.010"-.015" clearance between inner shoe facing and
brake drum. Then hold nut " B " and tighten lock nut
" C" securely.
4. Recheck both facing to drum clearances.
Propeller Shaft Parking Brake (Double Shoe Type)
The double shoe type parking brake is sim ilar to a
wheel brake with two brake shoes and riveted linings.
The shoes are operated by moving an offset cam between
the brake shoes by means of a mechanical lever. Adjust­
ment is sim ilar to the single shoe type whereby the
clearance between the brake shoe and drum should be
adjusted at the parking brake to give approximately a
. " clearance measured by feeler gauges.
0 1 0
HYDRAULIC BRAKE LINES
Hydraulic Brake Hose
These hoses require no maintenance other than peri­
odic inspection for damage from road hazards or other
like sources. See brake lines under Service Operations
for proper installation of brake lines.
NOTE:
A l w a y s disconnect hydraulic brake
hoses at frame bracket before hoses are torqued
at the wheel cylinder. Make certain that brake
hoses are not twisted.
Hydraulic Brake Tubing
Hydraulic brake tubing used on all trucks is a double
layer flexible steel, copper coated and tin plated tubing
which resists corrosion and also stands up under high
pressures developed when brakes are applied. Mainte­
nance of the tubing should consist of a periodic check on
the tubing; especially, in the event of rattles and/or
crimping or slow leakage due to possible stone damage,
loose connections, etc.
BRAKES 5-11
CHEVROLET TRUCK SERVICE M ANUAL