ACURA NSX 1991 Service Repair Manual

Oil Pressur e
Testing
If th e oi l pressur e warnin g ligh t stay s o n wit h th e engin e
running , chec k th e engin e oi l level . I f th e oi l leve l i s
correct :
1 . Remov e th e engin e oi l pressur e switch , an d instal l
a n oi l pressur e gauge .
2. Star t th e engine . Shu t i t of f immediatel y i f th e
gaug e register s n o oi l pressure . Repai r th e proble m
befor e continuing .
3 . Allo w th e engin e t o reac h operatin g temperatur e
(fa n come s o n a t leas t twice) . Th e pressur e shoul d
be:
Engin e Oi l Pressure :
A t Idle : 7 0 kP a (0. 7 kg/cm2, 1 0 psi )
minimu m
At 3,00 0 rpm : 35 0 kP a (3. 5 kg/cm2, 5 0 psi )
minimu m
• I f oi l pressur e i s
within specifications , replac e th e
oi l pressur e sende r an d recheck .
• I f oi l pressur e i s NO T withi n specifications , inspec t
th e oi l pum p (se e pag e 8-8) .
ENGIN E OI L PRESSUR ESWITCHMOUNTIN G HOL E
OIL PRESSUR E GAUG E ADAPTO R
(1/8 " - 28 , BSPT )
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Oil Pum p
Overhau l
NOTE:
• Us e ne w O-ring s whe n reassembling .
• Appl y oi l t o O-ring s befor e installation .
6 x 1. 0 m m6 N- m (0. 6 kg-m . 4 Ib-ft ) PUM
P COVE RInspection , pag e 8-8 , 8-9PUM P HOUSIN G
Inspection , pag e 8-8 , 8-9
OI L SEA LInstallation , pag e 8- 9Replace .
OUTER ROTO RInspection , pag e 8-8 , 8-9
SEALIN G BOL T 1 8 m m
5 0 N- m (5. 0 kg-m , 3 6 Ib-ft )
RELIE F VALV EValve mus t slid e freel y
i n housin g bore .
I f valv e i s scored ,
replac e it .
O-RIN GReplace .
SEALING BOL T 2 0 m m
4 0 N- m (4. 0 kg-m , 2 9 Ib-ft )
INNE
R ROTO R
Inspection , pag e 8-8 , 8-9
WASHE R
Replace .
VALV E SPRIN G
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Oil Pump
Removal/lnspection/lnstallation
1. Drain the engine oil. 2. Remove the timing belt (see page 6-15('91-'93)or('94-'96)).
3. Remove the dipstick and the pipe.
4. Remove the oil filter assembly.
5. Remove the oil pan.
6. Remove the oil screen.
7. Remove the baffle plate,
8. Remove the oil pass
pipe and the joint.
9. Remove the mounting bolts and the oil pump

assembly.

Replace.
O-RINGS
Replace.

OIL SCREEN OIL PASS PIPE

AND JOINT
BAFFLE PLATE

OIL PUMP
10. Remove the nine screws from the pump housing,

then separate the housing and cover.

11. Check the inner-to-outer rotor radial clearance.

Inner-to-Outer Rotor Radial Clearance
Standard (New): 0.05 – 0.21 mm (0.002 – 0.008 in)
Service Limit: 0.23 mm (0.009 in)

OUTER ROTOR

INNER ROTOR

12. Check the housing-to-rotor axial clearance. Housing-to-Rotor Axial Clearance
Standard (New): 0.02 – 0.07 mm
(0.001 – 0.003 in)

Service Limit: 0.12 mm (0.005 in)

PUMP HOUSING

OUTER ROTORProCarManuals.com

13. Chec k th e housing-to-oute r roto r radia l clearance .
Housing-to-Roto r Radia l Clearanc e
Standard (New) : 0.1 1 - 0.2 0 m m
(0.00 4 - 0.00 8 in )
Servic e Limit : 0.2 1 m m (0.00 8 in )
OUTE R ROTO R
PUMP HOUSIN G
14. Inspec t bot h rotors and th e pum p housin g fo r scorin g
o r othe r damage . Replac e th e oi l pum p assembl y i f
necessary .
1 5 . Remov e th e ol d oi l sea l fro m th e oi l pump .
16 . Gentl y ta p i n th e ne w oi l sea l unti l th e specia l too l
bottom s o n th e pump .
OIL SEA L DRIVE R07GAD-PH7020 1
OIL PUM P
17. Reassembl e th e oi l pump . Appl y liqui d thread-loc k
t o th e pum p housin g screws .
18 . Chec k tha t th e oi l pum p turn s freely .
19 . Appl y a ligh t coa t o f oi l t o th e sea l lip .
20 . Instal l th e tw o dowe l pin s an d ne w O-rin g o n th e
cylinde r block .
21 . Appl y liqui d gaske t t o th e cylinde r bloc k matin g
surfac e o f th e oi l pump .
NOTE:
• Use liqui d gasket , Par t No. 08718-0001 .
• Chec k tha t th e matin g surface s ar e clea n an d
dr y befor e applyin g liqui d gasket .
• Appl y liqui d gaske t evenly , i n a narro w bea d
centere d o n th e matin g surface .
• T o preven t leakag e o f oil , appl y liqui d gaske t t o
th e inne r thread s of the bol t holes .
PUMP HOUSIN G Appl
y liqui d
gaske t alon g th e
broke n line .
Do no t instal l th e part s i f fiv e minute s o r mor e
hav e elapse d sinc e applyin g liqui d gasket .
Instea d reappl y liqui d gaske t afte r removin g ol d
residue .
After assembly , wai t a t leas t 2 0 minute s befor e
fillin g th e engine with oil .
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Oil Pump

Removal/lnspection/lnstallation

22. Install the oil pump on the cylinder block.

23. Install the oil pass pipe and joint.

24. Install the baffle plate.

25. Install the oil screen.

SPECIAL BOLTS

8 x
1.25
x 45 mm

22 N-m
(2.2 kg-m,

16 Ib-ft)

Replace.

DOWEL PINS

OIL PASS

PIPE AND JOINT

OIL PUMP

Apply liquid gasket to

cylinder block mating

surface.

6 x 1.0 mm

12 N-m
(1.2 kg-m,

9 Ib-ft)

OIL

SCREEN
BAFFLE

PLATE

6 x 1.0 mm

12 N-m
(1.2 kg-m,

9 Ib-ft)
26. Apply liquid gasket to the oil pump and left side

cover mating areas as shown below.

Apply liquid gasket

to these points.

OIL PUMP

Apply liquid gasket

to these points.

27. Install the oil pan gasket and oil pan.

NOTE: Use a new oil pan gasket.
CYLINDER

BLOCK

GASKET

Replace.

OIL PAN
LEFT

SIDE

COVER

SPECIAL BOLTS

6 x 1.0 mm

12 N-m (1.2 kg-m, 9 Ib-ft)

Replace.ProCarManuals.com

28. Tighten bolts and nuts finger tight at six points as

shown below.

29. Starting with nut torque all bolts and nuts, in a

clockwise pattern in three steps.

NOTE: Excessive tightening can cause distortion of

oil pan gasket and oil leakage.

Torque: 14 N-m (1.4 kg-m, 10 lb-ft)ProCarManuals.com

Oil Cooler , Oi l Filte r Bas e
Illustrate d Inde x
NOTE :
• Use new O-rings when reassembling.
• Apply oil to O-rings before installation.
• Use liquid gasket, Part No. 08718-0001
.
OI L COOLE R CENTE R BOL T
5 0 N- m (5. 0 kg-m . 3 6 Ib-ft )
2 m m PI N
O-RIN GReplac e
SPECIA L BOLT S8 x 1.2 5 mm22 N- m (2. 2 kg-m ,16 Ib-ft )
Replace .
OI L FILTE R BAS E SPRIN
G
RELIE F VALV E
Valve mus t slid e freel y i n bol t bore .If valv e i s scored , replac e it .
ENGIN E OI L COOLE R
O-RINGReplace .
OIL FILTE R22 N- m (2. 2 kg-m ,16 Ib-ft )
Replacement , 8- 5 ENGIN
E OI L
PRESSUR E SWITC H
1 8 N- m (1. 8 kg-m , 1 3 Ib-ft )
1/ 8 in . BSP T (Britis h Standar d
Pip e Taper ) 2 8 Threads/inch .
Use prope r liqui d gasket .
8 x 1.2 5 mm22 N- m (2. 2 kg-m , 1 6 Ib-ft )
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Special Tools

Ref.
No.
Tool Number Description
Qty


Page Reference
9-4('91-'93) or ('94-'96),
5 ('94-'96),
O
2
Sensor Socket Wrench
07LAA – PT50101

1ProCarManuals.com

Intake Manifol d
Replacemen t
NOTE: Us e ne w O-ring s an d gasket s whe n reassembling .
CAUTION:
• Chec k fo r fold s o r scratche s o n th e surfac e o f th e gasket .
• Replac e wit h a ne w gaske t i f damaged .
6 x 1. 0 m m12 N- m (1. 2 kg-m , 9 Ib-ft )5 x 1. 0 m m8 N- m (0. 8 kg-m , 6 Ib-ft )
INTAK E AI R TEMPERATUR E
(IAT ) SENSO R
6 x 1. 0 m m12 N- m (1. 2 kg- m9 Ib-ft )
IGNITIO N CONTROL -
MODULE (ICM )
6 x 1. 0 m m12 N- m (1. 2 kg-m ,9 Ib-ft )
8 x 1.2 5 mm22 N- m (2. 2 kg-m ,16 Ib-ft )
THROTTL EBODY
INTAK E MANIFOL DPLATE
TOP COVE R
6 x 1. 0 m m.12 N- m (1. 2 kg-m , 9 Ib-ft )
EXHAUS T GA S RECIRCULATIO N(EGR) POR T
8 x 1.2 5 mm22 N- m (2. 2 kg-m , 1 6 Ib-ft )
INTAK E MANIFOL D
Replac e i f cracke d o r
i f matin g surface s ar e
damaged .
8 x 1.2 5 mm22 N- m (2. 2 kg-m ,16 Ib-ft ) INTAK
E AI R BYPAS S (IAB )
VALV E BOD Y
INTAK E MANIFOL D
CHAMBE R
8 x 1.2 5 mm22 N- m (2. 2 kg-m , 1 6 Ib-ft )
EG R PIP E
GASKET SReplace.
6 x 1. 0 m m12 N- m (1. 2 kg-m ,9 Ib-ft )INSULATO
R
WASHERReplace.
GASKE TReplace .
GASKETReplace .
GASKETReplace .
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Exhaust Manifol d
Replacemen t
NOTE: Us e ne w gasket s an d self-lockin g nuts .
FRON T PRIMAR Y
HEATE D OXYGE N SENSO R
(HO2S)45 N- m (4. 5 kg-m , 3 3 Ib-ft )
• B e carefu l no t t o damage .
• Us e th e specia l too l whe nremovin g an d installing .
8 x 1.2 5 mm22 N- m (2. 2 kg-m ,16 Ib-ft )
REAR PRIMAR YHO2S45 N- m (4. 5 kg-m ,33 Ib-ft )
• B e carefu l no t t o damage .
• Us e th e specia l too l whe n
removin g an d installing .
6 x 1 0 m m12 N- m (1. 2 kg-m ,9 Ib-ft )
SELF-LOCKIN GNUT8 x 1.2 5 mm34 N- m (3. 4 kg-m ,25 Ib-ft )
Appl y oi l t o th e
nu t threads .
Replace.
FRONT EXHAUS T MANIFOL D
8 x 1.2 5 mm22 N- m (2. 2 kg-m ,16 Ib-ft )
EXHAUS T MANIFOL DCOVER
EXHAUS TMANIFOL DCOVERS
8 x 1.2 5 mm22 N- m (2. 2 kg-m ,16 Ib-ft )
GASKE TReplace .
REAR EXHAUS T MANIFOL D
SELF-LOCKIN G NUT S
8 x 1.2 5 mm34 N- m (3. 4 kg-m ,25 Ib-ft )
Appl y oi l t o th e
nu t threads .
Replace.
6 x 1. 0 m m12 N- m (1. 2 kg-m ,9 Ib-ft )
GASKE TReplace .
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