ACURA NSX 1991 Service Repair Manual
Manufacturer: ACURA, Model Year: 1991, Model line: NSX, Model: ACURA NSX 1991Pages: 1640, PDF Size: 60.48 MB
Page 1541 of 1640

Transmission Assembly
Removal (cont'd)
19. Remove the intermediate shaft heat cover and the intermediate shaft mounting bolts.
20. Pry the intermediate shaft out of the differential. Pull and remove it.
NOTE:
Coat all precision finished surfaces with clean engine oil or grease. Tie plastic bags over the driveshaft ends.
INTERMEDIATE SHAFT
SUPPORT BASE
SET RING
Replace.
INTERMEDIATE SHAFT
21. Remove the parking brake cable holder and the Anti-lock Brake sensor wire clamp.
22. Scribe a reference mark on the flange of the adjusting bolt, adjusting cam and lower control arm.
23. Loosen the ball joint nut, then separate the toe control arm from the knuckle using the special tool (see section 18).
24. Remove the damper fork bolt.
25. Remove the bolts and lower control arm from the side beam.
26. Remove the left driveshaft from the differential.
27. Pry the driveshaft out of the differential. Pull and remove it.
NOTE:
Coat all precision finished surfaces with clean engine oil or grease.
Tie plastic bags over the driveshaft ends.
INTERMEDIATE SHAFT
MOUNTING BOLT
INTERMEDIATE SHAFT
HEAT COVER
DAMPER FORK BOLT
TOE CONTROL ARM
LOWER CONTROL ARM
ADJUSTING
BOLT
ADJUSTING
CAM
SET RING
Replace.
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Page 1542 of 1640

28. Remove the one of the upper control arm mounting bolts.
29. Remove the lower cover, change wire bracket and upper cover.
30. Remove the shift cable and select cable.
31. Remove the slave cylinder from the transmission. NOTE: Do not operate the clutch pedal once the slave
cylinder has been removed.
32. Remove the release fork from the clutch release hanger, then hang the release fork on the clutch housing.
Corrosion resistant bolt/nut
UPPER CONTROL ARM
DAMPER
SLAVE CYLINDER
ASSEMBLY
UPPER COVER
COTTER PIN
Replace.
SHIFT CABLE
UPPER ARM MOUNTING
BOLT
CHANGE WIRE
BRACKET
33. Remove the clutch housing cover.
34. Attach a chain hoist to the transmission hangers.
35. Place a jack under the transmission and raise the transmission just enough to take weight off mounts.
36. Remove the front engine mounting bolts on the transmission side and retighten the bolt on the engine side. CAUTION: Loosen the front engine mounting bolt on the engine side, but do not remove it. After removing the two
bolts on the transmission side, be sure to retighten the bolt on the engine side.
37. Remove the rear transmission mounting bolts and engine stiffener.
38. Remove the transmission housing mounting bolts.
39. Pull the transmission away from the engine until it clears the mainshaft, then lower it on the transmission jack.
SELECT CABLE
LOWER COVER
RELEASE FORK
Corrosion resistant bolt/nut
REAR TRANSMISSION
MOUNT
REAR TRANSMISSION
MOUNTING BOLT
TRANSMISSION JACK
TRANSMISSION HOUSING
MOUNTING BOLT
ENGINE STIFFENER
CLUTCH HOUSING
COVER
FRONT ENGINE MOUNTING
BOLT (Transmission side
)
FRONT ENGINE MOUNTING
BOLT (Engine side
)
TRANSMISSION HOUSING
MOUNTING BOLTSProCarManuals.com
Page 1543 of 1640

CLUTCH RELEASE HANGER
RELEASE HANGER SPRING
RELEASE BEARING GUIDE
40 x 68 x 12.5 mm OIL SEAL
Replace.
10 x 20 mm DOWL PIN
CLUTCH HOUSING
SPEED SENSOR
SENSOR DUMMY COVER O-RING
Replace.
HOLDER PLATE
REVERSE SHIFT FORK ASSEMBLY Disassembly/Reassembly, page
13-16
REVERSE IDLE GEAR SHAFT
ASSEMBLY Disassembly/Reassembly, page
13-15
OIL GUIDE RING
90 mm WASHER
BEARING OUTER RACE
DIFFERENTIAL ASSEMBLY See section 15
OIL GUIDE PLATE
44 x 72 x 23 mm NEEDLE BEARING
BEARING RETAINING PLATE
COUNTERSHAFT ASSEMBLY Index, page
13-29
MAINSHAFT ASSEMBLY
Index, page
13-23
75 mm SPRING WASHER
32 x 46 x 7 mm OIL SEAL
Replace.
TRANSMISSION MAGNET
SHIFT FORK ASSEMBLY Disassembly/Reassembly, page
13-22
OIL PUMP ASSEMBLY
Disassembly/Reassembly, page
13-37
CHANGE HOLDER ASSEMBLY
Disassembly/Reassembly, page
13-19
UPPER COVER
SELECT LEVER ASSEMBLY
Removel, page
13-17 Installation, page 13-43
REVERSE SHIFT ARM
14x20 mm DOWEL PHIS
14 x 20 mm DOWEL PIN
Clean all parts thoroughly in solvent and dry with compressed air.
Illustrated Index
Lubricate all parts with oil before reassembly.
NOTE:
This transmission uses no gaskets between the major housings; use P/N 08718 — 0001 sealant.
Assemble the housings within 20 minutes after applying the sealant and allow it to cure at least 30 minutes after
assembly before filling the transmission with oil.
Always clean the magnet whenever the transmission housing is disassembled.
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Page 1544 of 1640

BEARING OUTER RACE
75 mm THRUST SHIM
Selection.
CLAMP
BACK-UP LIGHT SWITCH
25 N·m (2.5 kg-m, 18 Ib-ft)
CLAMP
TRANSMISSION HANGER A
TRANSMISSION HANGER B
STAY
WASHER
Replace.
OIL FILLER PLUG
45 N·m (4.5 kg-m, 33 Ib-ft)
42 x 63 x 12.5 mm OIL SEAL
Replace.
WASHER
Replace.
DRAIN PLUG
40 N·m (4.0 kg-m, 29 Ib-ft) 36 mm SEALING BOLT
35 N·m (3.5 kg-m. 25 Ib-ft)
STRAINER COVER O-RING
Replace.
STRAINER SET SPRING
OIL PUMP STRAINER
14 mm SEALING BOLT
33 N·m (3.3 kg-m. 24 Ib-ft)
SPRING (L. 25 mm)
STEEL BALL (LARGE) 16 mm SEALING BOLT
42 N·m (4.2 kg-m, 30 Ib-ft) SPRING (L. 24.2 mm)
16 mm SEALING BOLTS
42 N·m (4.2 kg-m, 30 Ib-ft)
SPRING (L. 30 mm)
STEEL BALL (SMALL)
SHIFT LEVER ASSEMBLY
0 Removal, page
13-17
• Installation, page 13-43
NEUTRAL SWITCH
25 N·m (2.5 kg-m, 18 Ib-ft)
TRANSMISSION HOUSING
OIL GUIDE PLATE
82 mm THRUST SHIM
• Selection, page
13-41
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Page 1545 of 1640

Transmission Housing
Removal
NOTE: Place the clutch housing on two pieces of wood
thick enough to keep the mainshaft from hitting the
workbench.
1. Remove the back-up light switch, neutral switch
and speed sensor.
SPEED SENSOR
NEUTRAL
SWITCH
BACK-UP LIGHT SWITCH
2. Remove the sealing bolts, springs and steel balls.
3. Remove the upper cover, then remove the transmission housing attaching bolts.
4. Remove the 36 mm sealing bolt.
ATTACHING
BOLTS
36 mm SEALING BOLT
SEARING
BOLT
SPRING
STEEL BALL
UPPER COVER
OIL GUIDE
PLATE
THRUST SHIM
6. Separate the clutch housing from the transmission
housing.
7. Remove the thrust shim and oil guide plate from the
transmission housing.
SNAP RING
SNAP RING PLIER
5. Expand the snap ring on the countershaft ball bear-
ing and remove it from the groove using a pair of
snap ring pliers.ProCarManuals.com
Page 1546 of 1640

Transmission
Reassembly
SHIFT LEVER
3. Install the oil seal, select arm and select lever in the
clutch housing.
OIL SEAL
Replace.
SELECT LEVER
4. Install the differential assembly in the clutch housing.
DIFFERENTIAL ASSEMBLY
(cont'd)
1. Install the oil seal, shift arm and shift lever in the
transmission housing.
8 x 1.0 mm SPECIAL BOLT
32 N·m (3.2 kg-m, 23 Ib-ft) SPRING WASHERReplace.
SHIFT ARM
OIL SEAL
Replace.
2. Install the shift detent spring and spring set plate.
8 x 1.25 mm SPECIAL BOLT
26 N·m (2.6 kg-m, 19 Ib-ft)
SPRING SET PLATE
SHIFT DETENT SPRING
8 x 1.0 mm SPECIAL BOLT
32 N·m (3.2 kg-m, 23 Ib-ft)
SPRING WASHERReplace.
SELECT ARMProCarManuals.com
Page 1547 of 1640

Transmission
Reassenbly (cont'd)
5. Install the spring washer, then insert the mainshaft and countershaft into the shift forks and install
them as an assembly.
NOTE: Tape the mainshaft spline, before instal-
lation.
COUNTERSHAFT
ASSEMBLY
MAINSHAFT
ASSEMBLY
SPRING WASHER
SHIFT FORK
ASSEMBLY
6. Install the change holder assembly in the clutch
housing.
NOTE: Plate the interlocker finger in the groove of
the select arm.
6 x 1.0 mm SPECIAL BOLTS
15 N·m (1.5 kg-m, 11 Ib-ft)
CHANGE HOLDER
ASSEMBLY
INTERLOCKER FINGER
SELECT
ARM
REVERSE SHIFT FORK
ASSEMBLY
8. Shift the reverse shift fork to the driven gear side.
Lift the mainshaft assembly and reverse idle gear
shaft assembly, then install the reverse shift fork
assembly.
REVERSE IDLE GEAR
SHAFT ASSEMBLY
7. Lift the mainshaft assembly, then install the
reverse idle gear shaft assembly with the spring pin
matching the groove of the clutch housing.ProCarManuals.com
Page 1548 of 1640

9. Install the reverse shift arm.
6 x 1.0 mm SPECIAL BOLTS
15 N·m (1.5 kg-m. 11 Ib-ft)
REVERSE SHIFT ARM
10. Apply liquid gasket to the transmission mating sur-
face of the clutch housing.
NOTE: This transmission uses no gasket between
the major housings; use Honda Genuine liquid
gasket (P/N 08718 —0001)'. Assemble the housing
within 20 minutes after applying the liquid gasket
and allow it to cure at least 30 minutes after
assembly before filling it with oil.
(cont'd)
SHIFT PIECE
SHIFT ARM
Neutral
position.
SHIFT LEVER
a. Place the shift lever as a shown.
CLUTCH HOUSING
DOWEL PINS
TRANSMISSION
HOUSING
Groove
3RD/4TH SHIFT FORK SHAFT COLLAR
11. Install the dowel pins on the clutch housing.
12. Place the transmission housing over the clutch
housing, being careful to line up the shafts.
NOTE: Make sure the 3rd/4th shift fork shaft col-
lar mates with the 3rd/4th shift fork shaft.ProCarManuals.com
Page 1549 of 1640

Transmission
Reassembly (cont'd)
b. Lower the transmission housing, then place the
shift arm in the groove of the shift piece by turn-
ing the shift lever.
TRANSMISSION HOUSING
SHIFT LEVER
SHIFT
ARM
SHIFT PIECE
c. Check the operation of the shift lever.
14. Check that the snap ring is securely seated in thegroove of the countershaft bearing.
Dimension A as installed: 1.60–8.15 mm
(0.0630–0.3209 in)
COUNTERSHAFT
BEARING
SNAP RING
13. Lower the transmission housing with the snap ring
expanded and set the snap ring in the groove of thecountershaft bearing.ProCarManuals.com
Page 1550 of 1640

1 5. Tighten the transmission housing attaching bolts in
the numbered sequence shown below.
Torque: 45 N·m (4.5 kg-m, 33 Ib-ft)
16. Install the 36 mm sealing bolt.
NOTE: Apply Honda Genuine liquid gasket (P/N
08718-0001) to the flange.
17. Install the steel balls, spring and sealing bolts.
NOTE: Apply Honda Genuine liquid gasket (P/N
08718 — 0001) to the threads, but don't plug the
hole with liquid gasket.
18. Install the upper cover.
STEEL BALL
(3/8 in)
10 x
1.25
mm BOLTS
45 N·m
(4.5 kg-m,
33 Ib-ft)
14 x 1.0 mm SEALING BOLT
33 N·m (3.3 kg-m, 24 Ib-ft)
SPRING (L. 25 mm)
36 mm SEALING BOLT
35 N·m (3.5 kg-m, 25 Ib-ft)
STEEL BALL (5/16 in)
SPRING
(L. 30 mm)
SPRING
(L.
24.2
mm)
UPPER COVER
19. Install the back-up light switch and neutral switch.
NOTE: Apply Honda Genuine liquid gasket (P/N
08718 — 0001) to the threads.
20. Install the speed sensor.
6 x 1.0 mm BOLT
12 N·m (1.2 kg-m, 8.7 Ib-ft)
SPEED SENSOR
8 x 1.25 mm BOLT
26 N·m
(2.6
kg-m,
19 Ib-ft)
NEUTRAL SWITCH
25 N·m
(2.5
kg-m,
18 Ib-ft)
SPRING
(L. 30
mm)
16 x 1.0 mm
SEALING
BOLTS
42 N·m
(4.2 kg-m,
30 Ib-ft)
6 x 1.0 mm BOLTS
12 N·m (1.2 kg-m. 9 Ib-ft)
8 x 1.25 mm BOLTS
24 N·m (2.4 kg-m, 17 Ib-ft)
8 x 1.25 mm BOLTS
24 N·m (2.4 kg-m, 17 Ib-ft)
BACK-UP LIGHT SWITCH
25 N·m (2.5 kg-m, 18 Ib-ft)ProCarManuals.com