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SECTION 5D1
VACUUM BOOSTER
NOTICE: When fasteners are removed, always reinstall them at the same location from which they were
removed. If a fastener needs to be replaced, use the correct part number fastener for that application. If
the correct part number fastener is not available, a fastener o f equal size and strength (or stronger) m ay
be used. Fasteners that are not reused and those requiring thread locking compound will be called out.
The correct torque value m ust be used when installing fasteners that require it. If the above conditions
are not followed, parts or system damage could result.
CONTENTS
GENERAL DESCRIPTION
The vacuum booster is either a single or tandem dia
phragm vacuum suspended unit. During normal opera
tion, with the brake pedal released, manifold vacuum is
applied to both sides of the diaphragm(s). Applying the
brakes allows air at atmospheric pressure to enter one
side of the diaphragm(s). This pressure difference pro
vides the power assist.
Delco Moraine NDH vacuum boosters have a build
date on a small paper label glued to the front housing.
The first digit indicates the plant where it was built, and
the second digit indicates the year (1 means 1991, 2
means 1992, etc.). The last digits indicate the day it
was built (Example: 271 would mean the 271st day of
the production year).
BOOSTER ASSEMBLY
SING LE DIAPHRAGM
4*+
Remove or Disconnect (Figures 1 and 2)
A. Grasp outside edge of diaphragm support (15)
and diaphragm (14).
B. Hold pushrod (19) down against a hard surface.
Tool Required:
J 23456 Power Brake Booster Disassembly and
Reassembly Tool
1. Boot (1) and silencer (2).
2. Vacuum check valve (3) and grommet (4).
3. Front housing seal (5).
4. Scribe a mark across front and rear housings to aid
in reassembly.
5. Use J 23456 to apply force in a counterclockwise
direction to unlock housings (figure 1).
6. Return spring (9) and power piston group.
7. Power piston bearing (6) from rear housing (7).
8. Reaction body retainer (25).
9. Piston rod (10) and reaction retainer (11).
10. Filter (12) using an awl or similar tool.
11. Power piston and pushrod assembly (16).
Summary of Contents for S Series 1994
Page 1: ......
Page 11: ...VIEW A p n n n j VIEW C F7554 Figure 10 Hydra Matic 4L60 E Transmission I D Location...
Page 24: ...NOTES...
Page 26: ......
Page 69: ...NOTES...
Page 71: ...3 2 STEERING...
Page 73: ......
Page 84: ......
Page 102: ...40...
Page 130: ...NOTES...
Page 146: ...NOTES...
Page 162: ...NOTES...
Page 166: ...Figure 5 Removing the Pinion Flange Figure 6 Pressing the Drive Pinion from the Cage...
Page 178: ...Figure 3 Spreading the Differential Case Figure 4 Removing the Differential...
Page 190: ...NOTES...
Page 202: ...NOTES...
Page 206: ...F5785...
Page 212: ...B Button Moved Out of Bearing Bore F5791...
Page 228: ...NOTES...
Page 232: ......
Page 234: ......
Page 236: ...Adjuster 63 Bolt 64 Lock Figure 10 Turning the Adjuster Plug K3 Models...
Page 237: ...Figure 13 Removing the Pinion Seal 39 Bearing Cup Figure 16 Removing the Inner Bearing Cap...
Page 261: ...F7475...
Page 267: ...B Button Moved Out of Bearing Bore F5791...
Page 294: ...NOTES...
Page 300: ...NOTES...
Page 318: ...NOTES...
Page 322: ...SR207LN2 EDS...
Page 324: ......
Page 326: ...OVERHEAD OILING AND RETURN MAIN OIL GALLERY N30005 6A2 J EDS...
Page 368: ...103 153 127 V1200...
Page 370: ......
Page 372: ......
Page 374: ...F9375 Figure 7 Engine Lubrication Diagram Engines Without Balance Shaft...
Page 376: ...Figure 9 Engine Lubrication Diagram Engines With Balance Shaft...
Page 399: ...V2974...
Page 410: ......
Page 412: ...195 196 201 174 252 163 165 164 244 3706r3924...
Page 452: ......
Page 454: ...163 164 V1202...
Page 456: ...20 21x 302 210 4 0 41 2 5 2 5 1 2 51 4 2 e3 54 3 9 252 252 S 255 255 25 6 256 209 V1196...
Page 458: ...100 1 8 4 185 183 177 v 75 201 3706r1204...
Page 460: ......
Page 510: ......
Page 512: ...V2131...
Page 514: ...110 106 106 103 90 93 89 88 87 86 v 7 7 7 7 j A _ 111 f t 2 a a s 53 49 L 47 46 3706r4751...
Page 516: ...259 260 150 237 S lM 180 167180 J 1 82 183 170 169 1 1 78 1 7 9 213212 2 0 7 205 r i 3706r4752...
Page 566: ...NOTES...
Page 574: ...NOTES...
Page 618: ...SPECIAL TOOLS...
Page 620: ...NOTES...
Page 672: ......
Page 682: ......
Page 686: ......
Page 694: ...RH0213 4L60 E...
Page 695: ...657 659 m i J 8092 H J 34196 4 3 34196 5 657 658 665 J 23907 J 7004 1 J 8092 RH0214 4L60 E...
Page 696: ...J 8092 J 34196 4 33 31 J 8092 RH0215 4L60 E...
Page 697: ...SPECIAL TOOLS...
Page 698: ...SPECIAL TOOLS...
Page 758: ...RH0194 4L80 E...
Page 764: ......
Page 770: ...SPECIAL TOOLS...
Page 771: ...SPECIAL TOOLS CONT...
Page 772: ......
Page 775: ......
Page 776: ......
Page 785: ......
Page 804: ...NOTES...
Page 806: ......
Page 808: ......
Page 822: ...3707r5079...
Page 840: ......
Page 848: ...NOTES...
Page 852: ......
Page 860: ...F5435...
Page 866: ......
Page 878: ...F9167...
Page 882: ...16 FrontOutputShaft 18 DrivtQNr 19 DrivenGm t 20 DriveChain 22 FrontOutputBearing V2836...
Page 890: ...F9168...
Page 908: ......
Page 919: ......