1991 ACURA NSX engine

Engine Removal/Installatio n
Removal
Make sur e jack s an d safet y stand s ar e place d properl y
an d hois t bracket s ar e attache d t o th e correc t posi -
tion s o n th e engin e (se e sectio n 1 ).
• Mak e sur e th e ca r wil l no t rol l of f stand s an d fal l
whil e yo u ar e workin g unde r it .
CAUTION :
• Us e a fende r cove r (specia l tool ) t o avoi d damagin g
painte d surfaces .
• Unspecifie d item s ar e common .
• Unplu g th e wirin g connector s carefull y whil e holdin g
th e connecto r portio n t o avoi d damage .
• Mar k al l wirin g an d hose s t o avoi d misconnection .
Also , b e sur e tha t the y d o no t contac t othe r wirin g o r
hose s o r interfer e wit h othe r parts .
• I f th e groun d clearanc e need s t o b e increased , us e a
scissor s jac k an d instal l rubbe r spacer s i n th e coi l
spring s (se e sectio n 1 ).
• Pu t rubbe r pad s unde r th e jackin g point s whe n usin g
jack s o r safet y stand s t o avoi d damagin g th e bod y
(se e sectio n 1 ).
1 . Mov e th e sea t bottom s an d back s a s fa r forwar d a s
the y wil l go .
2. Remov e th e rea r hatc h assembl y an d engine cover
(se e sectio n 20 ).
3 . Disconnec t th e batter y negativ e termina l first , the n
the positiv e terminal . 4
. Remov e th e stru t brace .
COUPE :
STRUT BRAC E8 x 1.2 5 mm22 N- m (2. 2 kg-m ,16 Ib-ft )
NS X FENDE R
COVER07MAZ - SLOOOO A
NSX-T (ope n top) :
8 x 1.2 5 mm22 N- m (2. 2 kg-m , 1 6 Ib-ft )STRU T BRAC E
NSX FENDE R COVE R07MAZ-SLOOOO A
CORROSIO N RESISTAN T BOL T
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Engine Removal/Installatio n
Removal
5. Disconnec t th e fa n moto r connector , the n remov e
the engin e roo m fa n assembly .
ENGINE ROO MFAN
FAN MOTO R
CONNECTO R
6 x 1. 0 m m10 N- m (1. 0 kg-m , 7 Ib-ft )
6. Remov e th e rea r tri m panel s behin d th e passenger' s
seat , the n disconnec t fou r connector s fro m th e
engin e contro l modul e (ECM ) an d thre e connector s
fro m th e floo r wir e harness .
ENGINE WIR E
HARNES S
ECM
FLOO R WIR E
HARNES S
CORROSIO N RESISTAN T BOL T
7. Disconnec t th e spar k plu g voltag e detectio n modul e
connectors , ground cable an d engin e wir e harnes s
clamps .
SPARK PLU G VOLTAG EDETECTIO N MODUL ECONNECTOR S
GROUND
CABLE
ENGIN E WIR E
HARNES S CLAMP S
8. Disconnec t th e fue l pum p resisto r connector , injec -
to r resisto r connecto r an d groun d cable .
FUEL PUM P RESISTO R
CONNECTO R
GROUND CABL E
INJECTO R RESISTO R
CONNECTO R
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9. Relieve fuel pressure by loosening the service bolt
on the fuel filter about one turn (see section 11).
Do not smoke while working on the
fuel
system.
Keep open flame away from work
area. Drain fuel only into an approved container.
10. Remove the fuel feed pipe and fuel return hose.
11. Remove the wire harness cover, then remove the fuel pipe clamp.

22 N·m
(2.2 kg-m,
16 Ib-ft)

WIRE HARNESS

COVER
6 x 1.0 mm

12 N·m
(1.2 kg-m,

9 lb-ft)

FUEL FEED
PIPE

WASHERS
Replace.

FUEL RETURN

HOSE

12. Remove the brake booster vacuum hose and evapo- rative emission (EVAP) control canister hose.

BRAKE BOOSTER

VACUUM HOSE

EVAP CONTROL

CANISTER HOSE
13. Remove the expansion tank cap.

14. Raise the hoist to full height.
15. Drain the engine coolant (see page
10-5).
Loosen the drain plug from the radiator lower
tank. Remove two drain bolls from the water pipes.
Reinstall the drain bolts with new washers.
Loosen the front and rear engine drain bolts to
drain engine coolant from the cylinder heads.
Connect rubber hoses to the drain bolts.
16. Drain the transmission oil/fluid. Reinstall the drain plug with a new washer.
17. Drain the engine oil. Reinstall the drain plug with a
new washer.

18. Lower the hoist, then remove the air cleaner hous-

ing (see page 6-25 ('91-'93 Mode ls),or('95-'96 Models).

19. Disconnect two hoses, then remove the expansion

tank.

6 x 1.0 mm

10 N·m
11.0 kg-m,

7 lb-ft)

EXPANSION

TANK

WATER BYPASS

HOSES
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Engine Removal/Installation

Removal

20. Disconnect the engine wire harness connectors.

21. Remove the battery cable from the main fuse box.

ENGINE WIRE

HARNESS CONNECTORS

BATTERY

CABLE

6 x 1.0 mm

10 N-m
(1.0 kg-m,

7 Ib-ft)

22. Disconnect the throttle body 6P connector, and

remove the ground cable and starter cable.

STARTER CABLE
THROTTLE BODY

6P CONNECTOR

GROUND CABLE

CORROSION RESISTANT BOLT
23. Disconnect the two connectors from the emission

control box, then remove the control box.

• Do not disconnect the vacuum hoses.

6 x 1.0 mm

10 N-m (1.0 kg-m, 7 Ib-ft)

CONNECTORS

CONTROL BOX

24. Remove the radiator hoses and heater hose.

HEATER HOSE

RADIATOR

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Engine Removal/Installatio n
Removal
32. Remov e th e lef t an d righ t parkin g brak e cable s (se e
sectio n 19 ).
33 . Remov e th e rea r bea m ro d assembl y an d parkin g
brak e cabl e clamps . '
1 0 x 1.2 5 mm60 N- m (6. 0 kg-m ,43 Ib-ft )
12 x 1.2 5 mm95 N- m (9. 5 kg-m ,69 Ib-ft )
34. Remov e th e fron t engin e mount , the n remov e th e
fron t beam .
12 x 1.2 5 mm77 N- m (7. 7 kg-m , 5 6 Ib-ft )
Replace .
12 x 1.2 5 mm -95 N- m (9. 5 kg-m ,69 Ib-ft )
CORROSIO N RESISTAN T BOLT/NU T
35. Remov e th e A/ C compresso r (se e sectio n 22 ), the n
suspen d it fro m th e body .
NOTE :
• D o no t remov e th e compresso r hoses .
• D o no t le t th e compresso r han g b y it s hoses .
36 . Reinstal l th e fron t bea m an d fron t engin e mount .
Han g wit h wir e
or rope .
A/C COMPRESSO R
37. Remov e th e rea r brak e hoses , the n plu g th e brak e
pipe s wit h rubbe r cap s (se e sectio n 19 ).
38 . Disconnec t th e lef t rea r whee l senso r connector ,
then remov e th e whee l senso r wir e clamp s an d sta -
bilize r link .
6 x 1. 0 m m10 N- m (1. 0 kg-m ,7 Ib-ft )
LEFT REA R
WHEE L SENSO R
CONNECTO R
SELF-LOCKIN G NU T
12 x 1.2 5 mm95 N- m (9. 5 kg-m ,69 Ib-ft )Replace .
STABILIZE R
LIN K SELF-LOCKIN
G NU T
12 x 1.2 5 mm85 N- m (8. 5 kg-m , 6 2 Ib-ft )Replace .
REAR BEA M
RO D ASSEMBL Y
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39. Remov e th e righ t whee l senso r wir e clamp s an d
stabilize r link .
6 x 1. 0 m m10 N- m (1. 0 kg-m ,7 Ib-ft )
STABILIZE RLINK
SELF-LOCKIN G NU T
12 x 1.2 5 mm95 N- m (9. 5 kg-m ,69 Ib-ft )Replace .
SELF-LOCKIN G NU T12 x 1.2 5 mm85 N- m (8. 5 kg-m , 6 2 Ib-ft )
Replace .
40. Disconnec t th e fron t secondar y heate d oxyge n senso r
connector , the n remov e th e fron t exhaus t pip e A an d
fron t thre e wa y catalyti c converte r (TWC) .
41 . Separat e th e rea r TW C fro m th e rea r join t pipe .
SELF-LOCKIN G NUT S10 x 1.2 5 mm34 N- m (3. 4 kg-m , 2 5 Ib-ft )Replace .
GASKET SReplace.
GASKETReplace .SELF-LOCKIN G NU T •10 x 1.2 5 mm55 N- m (5. 5 kg-m , 4 0 Ib-ft )Replace .
42. Positio n th e specia l too l unde r th e car . Lowe r th e ca r
jus t abov e th e fixture . Wit h th e hel p o f a n assistant ,
attac h th e fixtur e t o th e subfram e wit h tw o 1 2 m m
nut s an d tw o 1 0 m m bolts .
LOOSEL Y INSTAL L TW O 1 2 m m
NUT S O N STUD S HER E
ENGINE REMOVAL /
INSTALLATIO N
FIXTURE07MAK-PR7020 A
LOOSEL Y INSTAL L ON E
1 0 m m BOL T HER E
43. Adjus t th e pad s o n th e fixtur e t o suppor t th e oi l pa n
an d transmissio n housing .
44 . Lowe r th e ca r s o th e fixtur e i s restin g o n it s caster s
(o r appropriat e platform) .
45 . Remov e th e tw o bolt s fro m th e sid e engin e moun t
nea r th e alternator . Pivo t th e mountin g bracke t int o
th e housin g o f th e body .
BODY SUPPOR TBRACKET
SIDE ENGIN EMOUNT
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Engine Removal/Installatio n
Removal
46. Remov e th e transmissio n mountin g bolt .
MOUNTIN G BOL T
TRANSMISSIO NMOUNT
47. Remov e th e twelv e subframe-to-bod y mountin g
bolts.
48. Rais e th e ca r a fe w inches .
49. Chec k tha t al l wire s an d hose s ar e disconnecte d
from th e engin e assembly .
50 . Rais e th e ca r completel y of f th e engine/suspensio n
assembly . Rol l th e assembl y fro m unde r th e car . NOTE
: Perfor m step s 5 1 thr u 5 4 onl y i f th e engin e
assembl y is t o b e remove d fro m th e subframe .
51 . Remov e th e adjustin g bol t an d flang e bolt , the n
separat e th e lowe r contro l ar m fro m th e subfram e
(se e sectio n 18 ).
52 . Remov e th e flang e bolt , the n separat e th e to e contro l
ar m fro m th e subfram e (se e sectio n 18 ).
CAUTION : Mak e sur e tha t th e referenc e mark s o n
th e contro l ar m ar e aligned .
53 . Remov e th e hea t shiel d for m th e intermediat e shaf t
bearin g support , the n remov e th e driveshaft s (se e
sectio n 16 ).
NOTE :
• Coa t al l precisio n finishe d surface s wit h clea n
engin e oil .
• Ti e plasti c bag s ove r th e driveshaf t ends .
54 . Attac h a chai n hois t t o th e engine .
Remov e th e fron t an d rea r moun t mountin g bolts ,
the n separat e th e engine from th e suspensio n an d
th e bea m assembly .
CAUTION : D o no t hi t th e engin e oi l coole r o n th e
rea r righ t bea m bracket .
FRONT MOUN T
REAR MOUN T
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Installation
Additional Torqu e Valu e Specifications :
NOTE : Fo r manifol d replacement , refe r t o sectio n 9 .
Engine Removal/Installation
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