Chevrolet Chevelle 1977 Repair Manual page 190

5-24
7
1. Pedal Push Rod
2. Pedal Rod Retainer
3. B o o t
4. Bracket N u t
5. Linkage Bracket
Booster Cover
6.
7. Cover to Housing Seal
8. In p u t Rod Seals
9. In p u t Rod and Piston Assy.
10. Spool Assem bly
11. Remove the booster assembly from the vise and while
holding the unit over a pan, separate the cover from the
housing. Remove the large seal ring from the groove in the
cover; discard the seal.
12. Remove the input rod and piston assembly, and the
spool assembly from the booster housing.
13. Remove the input rod seals from the input rod end,
and the piston seal from the piston bore in the housing;
discard the seals.
14. Remove the plunger, seat, spacer and ball from the
accum ulator valve bore in the flange of the booster housing.
Remove the "O" ring from the seat; discard the "O" ring.
15. Thread a screw extractor into the opening in the
check valve in the bottom of the accum ulator valve bore, and
remove the check valve from the bottom of the bore. Discard
the check valve and "O" ring.
NOTE:
Using a screw extractor damages the seat in the
check valve. A new charging valve kit must be installed
whenever the check valve is removed from the
accum ulator valve bore.
16. Use a 1/4" or a 5/16" spiral flute type screw
extractor to remove the tube seats from the booster ports.
OVERHAUL MANUAL
6 5
29 20
Plunger Seat
11.
12. " 0 " Ring Seal
Plunger
13.
14. Spacer
Check Valve Ball
15.
16. A c c u m u la to r Check Valve
17. " 0 " Ring Seal
Piston Seal
18.
19. Booster Housing
20. Tube Seat Inserts
Fig. 5-2E --Pow er B o o ste r C o m po n e n ts (T yp ica l)
4 3 2
21. O u tp u t Push Rod
22. Push Rod R etainer
Spool Spring
23.
Plug " 0 " Ring
24.
Spool Plug
25.
Snap Ring
26.
Piston R e tu rn Spring
27.
Spring R etainer
28.
Housing to Cover B olts
29.
Cleaning and Inspection
1. Clean all metal parts in a suitable solvent. Be careful
to avoid losing small parts.
2. Inspect the valve spool and the valve spool bore in the
booster housing for corrosion, nicks, scoring or other
damage. Discoloration of the spool or bore, particularly in
the grooves, is not harmful and is no cause for concern.
3. If the valve spool or the valve spool bore has nicks
or scoring that can be felt with a fingernail, particularly on
the lands, the entire booster should be replaced as an
assembly.
NOTE:
The clearance between the valve spool and the
spool bore of the housing assembly is important. Because
of this, the valve spool and the housing assembly make
up a selective assembly (the valve spool is selected to
m atch the spool bore).
4. Inspect the input rod and piston assembly for
corrosion, nicks, scoring or excessive wear. If the piston is
damaged, the input rod and piston assembly should be
replaced.
5. Inspect the piston bore in the booster housing for
corrosion, nicks, scoring or other damage. If the bore is
1