Chevrolet 10 Series 1970 Service Manual page 248

BRAKES 5-10
F i g . 1 8 — B r a k e
BRAKE PEDAL & PUSH ROD TRAVEL ADJUSTMENT
A definite pedal push
clearan ce must be maintained on the dash mounted main
cylin d er units. T h is cleara n ce is adjusted as follow s:
Threaded Rod Type Adjustm ent (Fig. 17)
1. A fte r the brake pedal and pedal bumper have been
assem bled, in sta ll the push rod and its attaching
parts. Tighten nut to 30 ft. lbs. torque.
obtain the c o r re c t clearan ce between the push rod
and the m aster cylin d er, adjust the push rod so that
the fr e e pedal tra v e l m easured at the center of the
pedal pad is approxim ately 1/8 inch (fig . 18).
2. A fte r tightening the locknut on the adjustable push
rod to 17-23 ft. lb s.
3. Stop light switch should be adjusted i f n ecessary, so
that e le c tric a l contact
.60 inches pedal pad tra ve l.
PARKING BRAKE ADJUSTMENTS
Rear W heel Parking Brake
Adjustment o f the cable connected " r e a r wheel ty p e "
parking brake used on 1/2, 3/4, and 1 ton m odels must be
p erfo rm e d each tim e the s e r v ic e brakes a re adjusted and
can be accom plished only when s e rv ic e brakes are in
adjustment.
The p ro p e lle r shaft parking brake used on all other
trucks op erates independent of the s e r v ic e brakes and
n ecessary adjustment o f e ith er the " band typ e" o r " shoe
ty p e" is co vered in this section.
FOOT PEDAL TYPE (Fig. 2 0 )
1. Jack up both re a r w heels.
2. Apply parking brake
position.
3. Loosen equ alizer check nut and tighten the adjusting
nut until a m oderate drag is fe lt when the rea r
wheels are rotated.
4. Tighten the check nut secu rely .
5. F u lly re le a s e parking brake and rotate the re a r
wheels. No drag should be present.
P e d a l F r e e M o v e m e n t
rod -to-m ain cylin d er piston
Then to
torque, recheck fr e e travel.
is made at approxim ately
1 notch fro m fu lly relea sed
F ig . 19— P ro p e lle r S haft Band Type P arking Brake
1. A n ch o r Screw
2. L o c a tin g B olt
3. Lock N u t
4. A d ju s tin g N u t
ORSCHELN LEVER TYPE (Figs. 2 1 -2 2 -2 6 -2 7 )
1. Turn adjusting knob on parking brake le v e r counter­
clockw ise to stop.
2. Apply parking brake.
3. Jack up both re a r wheels.
4. Loosen lock nut at interm ediate cable eq u a lizer and
adjust front nut to give light drag at re a r wheels.
5. R e-adju st parking brake le v e r knob to give a definite
sn a p -o ver-cen ter fe e l.
6. Fully re le a s e parking brake and rotate rea r wheels.
No drag should be present.
PROPELLER SHAFT BAND-TYPE PARKING
BRAKE ADJUSTMENT (Fig. 19)
1. P la ce hand le v e r in fu lly relea sed position. D is ­
connect brake rod on cable c le v is fro m operating
cams by rem oving cotter pin and c le v is pin.
2. R em ove lock w ire fro m anchor adjusting screw (1)
and turn anchor screw as n ecessa ry to obtain 0.010"
to 0.015" between lining and drum at anchor adjust­
ing screw location.
screw . Do not draw lock w ire up tight.
3. Loosen lock nut (3) on locating b olt (2) and tighten
adjusting nut (4) on locating bolt until there is a
clearan ce o f 0.020" between lo w e r end of lining and
drum. M easure clearance about 1 1/2 inch from end
o f lining. When c o r r e c t clearan ce is obtained, tighten
lock nut on locating bolt.
4. Loosen lock nut (6) on adjusting bolt (5) and tighten
adjusting nut (7) on adjusting bolt to obtain clearan ce
o f 0.020" between upper end o f lining and drum.
M easure clearan ce about 1 1/2 inch fro m end o f lin ­
ing. Tighten lock nut on adjusting bolt.
5. Adjust end on brake rod so that c le v is pin may be
fr e e ly in serted through operating cams and rod end.
Install c le v is pin and co tter pin, then tighten lock
nut on rod end.
5. A d ju s tin g B olt
6. Lock N u t
7 . A d ju s tin g N u t
Install lock w ire in anchor
CHEVROLET TRUCK SERVICE MANUAL