Chevrolet 1977 10 Series, Repair Manual, Page: 191 / 468

BRAKES
5-25
Fig. 5-3E --R em oving B o o s te r Pedal Rod (T y p ic a l)
damaged, the entire booster m ust be replaced as an assembly.
Assembly
CAUTION:
Be sure to keep parts clean until
reassembly. Re-wash at reassembly i f there is any
occasion to doubt cleanliness
-
such as parts
dropped or left exposed for eight hours or longer.
Lubricate all seals and metal friction points
with power steering fluid.
Whenever the booster is disassembled, all
seals, tube inserts and bracket nut should be
replaced. A ll o f these parts are included in a seal
kit. I f any o f the accumulator valve components are
damaged or lost, replace all valve components (all
are included in charging valve kit).
1. Position a N E W tube seat in each booster port and
screw a spare tube nut in each port to press the seat down
into the port. Do not tighten the tube nuts in the port as this
may deface the seats.
2. Remove the spare tube nuts and check for alum inum
chips in the ports. Be sure that any foreign m atter is removed.
3. Coat the piston bore and the piston seal with clean
power steering fluid, and assemble the N E W seal in the bore.
The lip of the seal must be toward the rear (away from the
m aster cylinder m ounting flange). Be sure the seal is fully
seated in the housing.
4. Lubricate the input rod end, N E W input rod seals
and Seal Installer Tool J-24553 with clean power steering
fluid. Slide the seals on the tool with the lip of the cups toward
the open end of the tool (fig. 5-4E).
5. Slide the tool over the input rod end and down to the
second groove; then slide the forward seal off the tool and
into the groove. Assemble the other seal in the first groove.
Be sure that both seals are fully seated.
6. Lubricate the piston and Piston Installing Tool J-
24551 with clean power steering fluid. Insert the large end
of the tool into the piston (fig. 5-5E), and slide the tool and
piston into the piston bore and through the piston seal.
INPUT ROD AND
PISTON
Fig. 5-4 E—I nsta 11 i ng In p u t Rod Seals
7. Assemble the N E W "O" ring onto the N E W
accum ulator check valve, and dip the assembly in clean
power steering fluid. Insert the check valve into the
accum ulator valve recess in the housing flange.
8. Assemble the new ball and spacer in the same recess.
9. Assemble the N E W "O" ring onto the charging valve
plunger seat and insert the plunger into the seat. Dip the
assembly in clean power steering fluid, and insert it into the
charging valve recess.
10. Dip the spool assembly in clean power steering fluid,
and insert the assembly into the spool bore in the housing.
Be sure that the pivot pins on the upper end of the input rod
lever assembly are engaged in the groove in the sleeve.
Remove Tool J-24551 from the piston assembly.
11. Position a N E W housing seal in the groove in the
housing cover. Then join the booster housing and cover and
secure with five screws. Tighten the screws to 18-26 ft. lbs.
using Special Socket J-25085.
CAUTION:
See "Caution " on Page 1 o f this section.
12. Assemble a N E W "O" ring seal on the spool plug.
Insert the spool spring and the spool plug in the forw ard end
Fig. 5-5 E--I nsta 11 i ng In p u t Rod and P is to n A s s e m b ly in to
B o o s te r (T y p ic a l)