1991 ACURA NSX Service Repair Manual

Mainshaft Thrust Shim

Adjustment

1. Remove the thrust shim and oil guide plate from the

transmission housing.

2. Install the mainshaft in the transmission housing.

NOTE: Do not install the clutch housing side ball

bearing.

3. Measure distance between the end of the

transmission housing and mainshaft.

NOTE:

• Use a straight edge and feeler gauge.

• Measure at three locations and average the

readings.

4. Set the mainshaft ball bearing in the clutch hous-

ing, and measure distance between the

surfaces of the clutch housing and the bearing in-

ner race.

NOTE:

• Use a straight edge and feeler gauge.

• Measure at three locations and average the

readings.

• Do not install the spring washer.
5. Select the proper thrust shim on the basis of the

following calculations.

NOTE: Do not use more than two thrust shims.

(Basic Formula)

A + B — 0.99 mm = shim thickness (max.)

A + B - 1.06 mm = shim thickness (min.)

A - C - 0.99 mm = shim thickness (max.)

A - C - 1.06 mm = shim thickness (min.)

82 mm THRUST SHIM

NOTE: Clean all the parts thoroughly before installation

6. Install the oil guide plate and thrust shim into the

transmission housing.

TRANSMISSION

HOUSING

THRUST SHIM

OIL GUIDE PLATE

13-41ProCarManuals.com

Mainshaft Thrus t Shi m
Adjustmen t
7. Instal l th e bal l bearin g ont o th e mainshaf t usin g th e
specia l tools , the n instal l th e 7 5 m m sprin g washe r
an d mainshaf t assembl y int o th e clutc h housing .
DRIVER, 4 0 m m I.D .07746 - 0030100
ATTACHMENT , 3 5 m m I.D .07746 - 0030400
BAL L BEARIN G
8. Instal l th e transmissio n housing .
Torque : 4 5 N- m (4. 5 kg-m , 3 3 Ib-ft )
9. Chec k th e thrus t clearanc e in th e manne r describe d
below.
NOTE : Carr y ou t th e measuremen t a t norma l roo m
temperature .
a . Slid e th e mainshaf t bas e ove r th e mainshaft ,
b . Attac h th e mainshaf t holde r t o th e mainshaf t a s
follows :
• Back-ou t th e mainshaf t holde r bol t an d
loose n th e tw o he x bolts .
• Fi t th e holde r ove r th e mainshaf t s o it s li p i s
toward s th e transmission .
• Alig n th e mainshaf t holder' s li p aroun d th e
groov e a t th e insid e of the mainshaf t splines ,
then tighte n th e he x bolts .
HEX BOL T
MAINSHAFT
HOLDER BOL T
MAINSHAF THOLDER07GAJ - PG20110
MAINSHAF T BAS E07GAJ - PG20130
c. Sea t th e mainshaf t full y b y tappin g it s en d
wit h a plasti c hammer .
d . Threa d th e mainshaf t holde r bol t i n unti l i t
jus t contact s th e wid e surfac e o f th e main -
shaf t base .
e . Zer o a dia l gaug e o n th e en d o f th e mainshaft .
DIAL GAUG E
f. Tur n th e mainshaf t holde r bol t clockwise ; sto p
turnin g whe n th e dia l gaug e ha s reache d it s
maximu m movement . Th e readin g o n dia l
gauge i s th e amoun t o f mainshaf t en d play .
CAUTION : Turnin g th e shaf t holde r bol t mor e
tha n 6 0 degree s afte r th e needl e o f th e dia l
gaug e stop s movin g ma y damag e th e
transmission .
g. I f th e readin g i s withi n th e standard , th e
clearanc e is correct .
I f th e readin g i s no t withi n th e standard , rechec k
th e shi m thickness .
Standard :
0.14-0.21 mm (0.006-0.00 8 in)
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Transmission

Reassembly

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 WASHER

SHIFT ARM

TRANSMISSION HOUSING

SHIFT LEVER

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
3. Install the oil seal, select arm, and select lever in

the clutch housing.

8 x 1.0 mm SPECIAL BOLT

32 N-m (3.2 kg-m, 23 Ib-ft)

SPRING WASHER

SELECT ARM

OIL SEAL

Replace.

CLUCH

HOUSING
SELECT LEVER

4. Install the differential assembly into the clutch

housing.

DIFFERENTIAL ASSEMBLY

CLUTCH HOUSINGProCarManuals.com

Transmission

Reassembly

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 splines before instal-

lation.

COUNTERSHAFT

ASSEMBLY

MAINSHAFT

ASSEMBLY

SPRING WASHER
SHIFT FORK

ASSEMBLY

Tape the main-

shaft splines.

6. Install the change holder assembly in the clutch

housing.

NOTE: Place the interlock 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)

SELECT

ARM
CHANGE HOLDER

ASSEMBLY

INTERLOCK FINGER
7. Lift the mainshaft assembly, then install the

reverse idle gear shaft assembly with the spring pin

matching the groove of the clutch housing.

REVERSE IDLE GEAR

SHAFT ASSEMBLY

SPRING PIN

GROOVE

8. Shift the reverse synchro sleeve to the driven gear

side. Lift the mainshaft assembly and reverse idle

gear shaft assembly, then install the reverse shift

fork assembly.

REVERSE SHIFT FORK

ASSEMBLYProCarManuals.com

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 surface of the transmis-

sion housing mating with the clutch housing as

shown.

NOTE:

• Use liquid gasket (P/N 08718-0001).

• Remove any dirt or oil from the sealing surface.

• Seal the entire circumference of the bolt holes to

prevent oil leakage.

• If 20 minutes have passed after applying liquid

gasket, reapply it and assemble the housings.

• After assembly, wait at least 30 minutes before

refilling with oil.
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.

3RD/4TH SHIFT FORK SHAFT COLLAR

TRANSMISSION

HOUSING

TRANSMISSION

HOUSING

DOWEL PINS
CLUTCH HOUSING

a. Place the shift lever as a shown.

SHIFT LEVER

Neutral

position.

SHIFT ARM

SHIFT PIECEProCarManuals.com

Transmission

Reassembly

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.
13. Lower the transmission housing with snap ring

pliers, and set the snap ring in the groove of the

countershaft bearing.

SNAP RING

14. Check that the snap ring is securely seated in the

groove of the countershaft bearing.

Dimension A as installed: 1.60—8.15 mm

(0.063-0.321 in)
COUNTERSHAFT

BEARINGProCarManuals.com

1 5 . Tighte n th e transmissio n housin g attachin g bolt s i n
a crisscros s patter n in severa l step s a s show n below .
Torque : 4 5 N- m (4. 5 kg-m , 3 3 Ib-ft )
16 . Instal l th e 3 6 m m sealin g bolt .
NOTE :
Apply liquid gaske t (P/ N 08718-0001 ) to
th e threads .
17 . Instal l th e stee l balls , springs , an d sealin g bolts .
NOTE : Appl y liqui d gaske t (P/ N 08718-0001 ) t o
th e threads , bu t don' t plu g th e hol e with liquid
gasket .
STEEL BAL L(3/8 in)
14 x 1. 0 m m SEALIN G BOL T33 N- m (3. 3 kg-m , 2 4 Ib-ft )
SPRIN G (L . 2 5 mm )
3 6 m m SEALIN G BOL T
3 5 N- m (3. 5 kg-m , 2 5 Ib-ft )
SPRIN G
(L. 24. 2 mm ) 12 x 1. 0 m m
SEALIN G BOL T22 N- m (2. 2 kg-m ,16 Ib-ft )
STEE L BAL L(5/16 in)
16 x 1. 0 m mSEALIN G
BOL T COM P
42 N- m(4.2 kg-m , 3 0 Ib-ft )
18. Instal l th e back-u p ligh t switc h an d neutra l positio n
switch.
NOTE: Appl y liqui d gaske t (P/ N 08718-0001 ) t o
the threads .
19. Instal l th e differentia l spee d senso r an d vehicl e spee d
senso r (VSS) .
VSS(O-RIN G Replace. ) NEUTRA
L POSITIO N
SWITCH25 N- m (2. 5 kg-m ,18 Ib-ft )
DIFFERENTIA L
SPEE D SENSO R
BACK-UP LIGH T SWITC H
2 5 N- m (2. 5 kg-m , 1 8 Ib-ft )
A: 8 x 1.2 5 mm24 N- m (2. 4 kg-m , 1 7 Ib-ft )B: 8 x 1.2 5 mm26 N- m (2. 6 kg-m , 1 9 Ib-ft )C: 6 x 1. 0 m m12 N- m (1. 2 kg-m , 9 Ib-ft )
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Transmission Assembl y
Installatio n
NOTE:
• Chec k tha t th e tw o dowe l pin s ar e installe d i n th e clutc h housing .
• Us e onl y Supe r Hig h Tem p Urea Greas e (P/N 08798-9002) .
1. Plac e th e transmissio n o n th e transmissio n jack , an d rais e it t o th e engin e level .
2 . Se t th e releas e for k t o th e clutc h housing .
3 . Instal l th e tw o transmissio n housin g mountin g bolt s an d engin e stiffener .
4. Instal l th e thre e rea r transmissio n mountin g bolts .
5. Loose n th e fron t engin e mountin g bolt , the n instal l th e tw o fron t engin e
mountin g bolt s t o th e transmissio n side .
6 . Remov e th e transmissio n jack .
7 . Instal l th e clutc h housin g cover .
DOWE L PIN S
(P/N 08798-9002 )
REAR TRANSMISSIO NMOUNTING BOLT S12 x 1.2 5 mm105 N- m(10. 5 kg-m , 7 6 Ib-ft )
TRANSMISSIO NJACK
TRANSMISSIO N HOUSIN GMOUNTIN G BOLT S12 x 1.2 5 mm65 N- m (6. 5 kg-m , 4 7 Ib-ft )
FRON T ENGIN EMOUNTIN G BOL T10 x 1.2 5 mm60 N- m (6. 0 kg-m , 4 3 Ib-ft )
8 x 1.2 5 mm22 N- m (2. 2 kg-m , 1 6 Ib-ft )
6 x 1. 0 m m12 N- m (1. 2 kg-m ,9 Ib-ft )
CLUTC H HOUSIN GCOVER10 x 1.2 5 mm45 N- m (4. 5 kg-m , 3 3 Ib-ft )
TRANSMISSIO N HOUSIN G MOUNTIN G BOL T12 x 1.2 5 mm65 N- m (6. 5 kg-m , 4 7 Ib-ft )
8. Instal l th e releas e for k i n th e releas e hanger , the n instal l th e slav e cylinder .
9. Connec t th e shif t cabl e an d selec t cable .
CAUTION : Tak e car e no t t o ben d th e cables .
10 . Instal l th e uppe r cover , chang e wir e bracke t an d lowe r cover .
11 . Instal l th e uppe r contro l ar m mountin g bolt .
Corrosio n resistan t bolt/nu t
8 x 1.2 5 mm22 N- m (2. 2 kg-m ,16 Ib-ft )
COTTE R PI NReplace .
SLAVE CYLINDE R
6 x 1. 0 m m12 N- m (1. 2 kg-m ,9 Ib-ft )
CHANG EWIREBRACKE T
LOWERCOVER
8 x 1.2 5 mm 6 x 1. 0 m m26 N- m (2. 6 kg-m , 1 9 Ib-ft ) 1 2 N- m (1. 2 kg-m , 9 Ib-ft )
UPPE R CONTRO L AR M MOUNTIN G BOL T10 x 1.2 5 mm60 N- m (6. 0 kg-m , 4 3 Ib-ft )
(P/N 08798-9002 )
Corrosion resistan t bolt/nu t
UPPER COVE R
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