ACURA NSX 1997 Service Repair Manual

Timing Bel t
Inspectio n
Remove th e ignitio n coi l cover s an d harnes s clamps .
Disconnec t th e connectors , the n remov e th e ignitio n
coils .
Remov e th e cylinde r hea d covers .
Inspec t th e timin g bel t fo r crack s an d coolan t o r oi l
soaking .
NOTE:
• Replac e th e bel t i f coolan t o r oi l soaked .
• Remov e an y oi l o r solven t tha t get s o n th e belt .
Inspec t thi s are a
fo r wear .
Rotate pulle y an d
Inspec t belt .
Tensio n Adjustmen t
CAUTION:
• Alway s adjus t timin g bel t tensio n wit h th e engin e cold .
• D o no t rotat e th e crankshaf t whe n th e adjustin g bol t
i s loos e (th e timin g bel t wil l ski d ove r th e teet h o f
th e rea r intak e camshaf t pulley) .
• Adjus t th e bel t tensio n onl y whe n th e bel t ha s bee n
remove d an d reinstalle d o r replaced .
NOTE:
• Tensione r i s spring-loade d t o appl y prope r tensio n t o
th e bel t automaticall y afte r makin g th e followin g
adjustment .
• Inspec t th e timin g bel t befor e adjustin g th e bel t
tension .
• Alway s rotat e th e crankshaf t clockwise . Rotatin g i t
counterclockwis e ma y resul t i n imprope r adjustmen t
o f th e bel t tensio n o r caus e th e bel t t o jum p a toot h
o n th e camshaf t pulleys .
1. Instal l th e timin g bel t wit h th e No . 1 pisto n a t TD C
(see page s 6-18 , 6-19 ).
2 . Remov e th e slac k i n th e sequenc e o f an d
by turnin g eac h camshaf t pulle y slightly .
3 . Loose n th e timin g bel t adjustin g bol t 180 ° (th e slac k
at shoul d b e eliminated) .
Then, tighte n th e timin g bel t adjustin g bolt .
4. Verif y tha t No . 1 pisto n i s a t TD C (se e pag e 6-19 ).
5 . Rotat e th e crankshaf t clockwis e nin e teet h o n th e
camshaf t pulle y (Th e blu e mar k o n th e crankshaf t pul -
le y shoul d lin e u p wit h th e pointe r o n lowe r cover. )
6 . Loose n th e timin g bel t adjustin g bolt .
7 . Retighte n th e adjustin g bolt , torqu e t o 4. 2 N- m (4. 3
kgf-m , 3 1 Ibf-ft) .
Directio nof rotatio nPOINTE R O NLOWE R COVE R
ADJUSTING BOL T
42 N- m (4. 3 kgf-m ,
3 1 Ibf-ft )
BLUE MAR K
TDC MAR K
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Removal
NOTE:
• Befor e removin g th e belt , tur n th e crankshaf t pulle y
s o th e No . 1 pisto n i s a t to p dea d cente r (TDC ) (se e
pag e 6-19 ).
• Inspec t th e wate r pum p afte r removin g th e timin g
bel t (se e pag e 10-11 ).
• I f i t i s t o b e reused , mar k th e directio n o f rotatio n o n
th e belt .
• Replac e th e timin g bel t a t 105,00 0 mile s (168,00 0 km )
accordin g t o th e maintenanc e schedul e (norma l con -
ditions/sever e conditions) . I f th e vehicl e i s regularl y
driven i n on e o r mor e o f th e followin g conditions ,
replace th e timin g bel t a t 60,00 0 mile s (U.S.A. )
100,00 0 k m (Canada) .
— In ver y hig h temperature s (ove r 110°F , 43°C) .
— In ver y lo w temperature s (unde r -20°F , -29°C) .
1 . Disconnec t th e batter y negativ e termina l first , the n
th e positiv e terminal .
2 . Remov e th e righ t rea r wheel/tire .
3 . Remov e th e engin e oi l coole r bas e assembly .
NOTE : D o no t disconnec t th e hoses .
O-RINGReplace .
4. Remov e th e stru t brac e (se e pag e 5-3 ).
5 . Remov e th e intak e manifol d plat e an d to p cove r (se e
pag e 6-26 ). 4
. Remov e th e ignitio n coi l covers , th e injecto r cove r
an d th e wir e harnes s covers .
5 . Remov e th e ignitio n coil s an d th e connectors .
NOTE:
• Ther e ar e fron t an d rea r ignitio n coil s an d covers .
The y ca n b e identifie d b y th e mar k F F (front ) o r
RR (rear ) printe d o n them .
• Whe n installin g fron t an d rea r ignitio n coi l covers ,
attac h a rubbe r sea l t o th e intak e side .
HARNES SCOVERS
IGNITION COI LCOVE R
CONNECTO R
IGNITION COI L
6. Remov e th e expansio n tank .
NOTE : D o no t disconnec t wate r hoses .
EXPANSIO N TAN K
(cont'd )
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Timing Bel t
Remova l (cont'd )
7. Remov e th e breathe r hos e an d th e ai r cleaner hous-
in g (se e pag e 6-26 ).
8 . Disconnec t th e alternato r connecto r an d th e termi -
nal.
9. Remov e th e cover , adjustin g bolt , th e mountin g bol t
an d mountin g nut , the n remov e th e alternato r bel t
an d th e alternator .
COVER
ADJUSTIN GBOLT
ALTERNATO RBELT
12. Remov e th e transmissio n moun t (se e pag e 5-10 ).
13 . Instal l a brac e unde r th e engine , the n til t th e engin e
approximatel y 5 ° usin g a jack .
NOTE : Mak e sur e t o plac e a cushio n betwee n th e
oi l pa n an d th e jack .
14 . Remov e th e alternato r bracke t stiffene r an d dipstick /
pipe .
ALTERNATO R BRACKE TSTIFFENE R
DIPSTICK PIP E
10. Remov e th e cylinde r hea d covers .
• Refe r t o page s 6-49 , 6-5 0 whe n installing .
11 . Remov e th e tw o bolt s fro m th e sid e engin e moun t
nea r th e alternato r bracket . Pivo t th e mountin g bracke t
int o th e housin g o f th e body .
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15. Loose n th e idle r pulle y cente r nu t an d adjustin g nut ,
the n remov e th e ai r conditionin g (A/C ) compresso r
belt .
ADJUSTIN GNUT
A/C COMPRESSO RBELT
16. Remov e th e crankshaf t pulle y (se e pag e 6-12 ).
17 . Remov e th e rubbe r sea l fro m th e adjustin g bolt ,
the n remov e th e middl e cover s an d lowe r cover .
LOWE R COVE R
RUBBE R SEA L
MIDDL E COVE R
COLLA R
IDLER PULLE YASSEMBL Y
18. Loose n th e adjustin g bol t 180 ° turn . Pus h th e ten -
sione r t o remov e tensio n fro m th e timin g belt , the n
retighte n th e adjustin g bolt .
ADJUSTIN G BOL T
D o no t remove . Whe n
adjusting , loose n
it 180° .
19. Remov e th e timin g bel t fro m th e pulleys .
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Timing Belt

Installation

Install the timing belt in the reverse order of removal;

Only key points are described here.

NOTE: Clean the middle and lower covers before instal-

lation.

1. Set the timing belt drive pulley so that the No. 1 pis-

ton is at top dead center (TDC). Align the A mark on

the teeth side of the timing belt drive pulley to the

pointer on the oil pump.

POINTER

MARK

KEY

TIMING BELT

DRIVE PULLEY

Clean.

2. Set the front camshaft pulleys so that the No. 1 pis-

ton is at TDC. Align the TDC marks on the front

exhaust camshaft pulley and front intake camshaft

pulley to the pointer on the back cover.

Pointer on the

back cover.

FRONT INTAKE

CAMSHAFT PULLEY
FRONT EXHAUST

CAMSHAFT PULLEY

TDC MARKS
3. Set the rear camshaft pulleys so that the No. 1 pis-

ton is at TDC. Align the TDC mark on the rear intake

camshaft pulley to the pointer on the back cover.

Align the rear exhaust camshaft pulley one half

tooth clockwise past TDC.

REAR EXHAUST

CAMSHAFT PULLEY
Pointer on the

back cover.
REAR INTAKE

CAMSHAFT PULLEY

TDC MARKS

4. Install the timing belt tightly in the sequence shown.

Timing belt drive pulley (crankshaft)

Adjusting pulley Front exhaust camshaft pulley

Front intake camshaft pulley Water pump

pulley Rear intake camshaft pulley Rear

exhaust camshaft pulley.

NOTE: Make sure the timing belt drive pulley and

camshaft pulleys are at TDC.

5. Tension the timing belt between the pulleys in the

sequence A to E as shown below.ProCarManuals.com

6. Adjus t th e timin g bel t (se e pag e 6-14 ).
7 . Instal l th e lowe r cove r an d middl e covers .
8 . Instal l th e crankshaf t pulley , the n tighte n th e pulle y
bol t (se e pag e 6-12 ).
9 . Chec k th e crankshaf t pulle y an d th e camshaf t pul -
ley s a t TDC .
NOTE : T o chec k th e camshaft , tr y t o inser t 5. 0 m m
pi n punche s a s show n whe n th e camshaf t i s a t TDC .
TDC MAR K(White paint )
TDC MARK S
REAR:
TDC MAR K TD
C MAR K
MIDDL E COVE R
5.0 m mPIN PUNCHE S
MIDDLE COVE R TD C MARK S
10. I f a camshaf t i s no t positione d a t TDC , remov e th e
timin g bel t an d adjus t th e positionin g followin g th e
procedur e o n pag e 6-18 , the n reinstal l th e timin g
belt .
11 . Afte r installation , adjus t th e tensio n o f eac h belt .
• Se e sectio n 2 3 fo r alternato r bel t tensio n adjust -
ment .
• Se e sectio n 2 2 fo r A/ C compresso r bel t tensio n
adjustment .
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CKP/CYP Senso r
Replacemen t
NOTE: Tur n th e crankshaf t s o tha t th e No . 1 pisto n i s a t
to p dea d cente r (se e pag e 6-19 ).
1 . Remov e th e timin g bel t (se e pag e 6-15 ).
2 . Remov e th e fron t intak e an d exhaus t camshaf t
pulleys .
3 . Remov e th e bac k cover .
4 . Remov e th e CKP/CY P senso r fro m th e fron t
cylinde r head . 5
. Instal l th e CKP/CY P senso r i n th e revers e orde r o f
removal .
• Refe r t o pag e 6-1 8 an d 6-19 , whe n installin g th e
timin g belt .
FRON T INTAK ECAMSHAF T PULLE YCKP/CY PSENSOR
LOWER COVE R
FRONTCAMSHAFT S
TIMINGBELT
FRON T EXHAUS TCAMSHAF T PULLE Y
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Cylinder Heads

Illustrated Index

CAUTION: To avoid damage, wait until the engine coolant temperature drops below 100°F (38°C) before removing the cylin-

der head.

NOTE: Use new O-rings and gaskets when reassembling.

Prior to reassembling, clean all the parts in solvent, dry them, and apply lubricant to any contact parts.

CAMSHAFT HOLDER

O-RING

Replace.
CAMSHAFT HOLDER

PLATE

CKP/CYP SENSOR

RUBBER SEALS

Replace when damaged

or deteriorated.

BACK COVER
Apply oil to the bolt threads.

FRONT INTAKE

CAMSHAFT

RUBBER SEALS

Replace for oil

leakage.

FRONT EXHAUST

CAMSHAFT

DOWEL PIN

CAMSHAFT PULLEY

(cont'd)ProCarManuals.com

Cylinder Head s
Illustrate d Inde x (cont'd )
CAUTION : T o avoi d damage , wai t unti l th e engin e coolan t temperatur e drop s belo w 10 0°F (3 8°C) befor e removin g th e cylin -
de r head .
NOTE : Us e ne w O-ring s an d gasket s whe n reassembling .
Prio r t o reassembling , clea n al l th e part s i n solvent , dr y them , an d appl y lubrican t t o an y contac t parts .
EXHAUS T GA SRECIRCULATIO N (EGR ) VALV E
REA R VARIABL E VALV E TIMIN G
AN D VALV E LIF T ELECTRONI C CONTRO L
SYSTE M (VTEC ) SOLENOI D VALV E
Troubleshooting , pag e 6- 3
FILTE R
Replace . ENGIN
E COOLAN T
TEMPERATUR E (ECT ) SENSO R
FRON T VTE C SOLENOI D VALV E
Troubleshooting , pag e 6- 3
SEALIN G BOLT S
4 9 N- m (5. 0 kgf-m ,
36 Ibf-ft )
OIL PRESSUR E
GAUG E SENDIN G
UNIT ( sectio n 23 )
DOWE L PI N
O-RIN G
Replace .
RADIATOR FAN CONTRO L SENSO R
2 7 N- m (2. 8 kgf-m , 2 0 Ibf-ft )
ROCKE R SHAF T
OI L CONTRO L
ORIFICERemov e wit h 5 m mbol t an d clean .
ROCKE R AR M ASSEMBL Y
(PRIMARY , MID , SECONDARY )
Inspection , page s 6-33 , 6-3 4
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INTAKE VALV E
SPRIN G OUTE R
CYLINDE R HEA D BOL T
M/T: 11 x 1. 5 m m96 N- m (9. 8 kgf-m , 7 1 Ibf-ft )A/T: 11 x 1. 5 m m76 N- m (7. 8 kgf-m , 5 6 Ibf-ft )Apply engin e oi l t oth e bol t threads .
INTAKE VALV E
SPRIN G INNE R
VALV E SEA L
VALV E GUID E
LOS T MOTIO N
ASSEMBL Y VALV
E KEEPER S
SPRIN G RETAINE R
VALV E SPRIN G
SEAT
CYLINDE R HEA D
GASKE T
Replace . CYLINDE
R HEA D BOLT S
M/T: 11 x 1. 5 m m96 N- m (9. 8 kgf-m , 7 1 Ibf-ft )A/T: 11 x 1. 5 m m76 N- m (7. 8 kgf-m , 5 6 Ibf-ft )Apply engin e oi l t o
th e bol t threads .
VALV E SPRIN G SEA T
EXHAUS T VALV E
SPRING
SPRIN G RETAINE R
VALV E KEEPER S
VALV E SEA L
VALV E GUID E
LOS T MOTIO N
ASSEMBL YTest, 6-3 3
CYLINDE R HEA D
GASKE TReplace .
DOWEL PI N
OI L CONTRO L ORIFIC E
Remove wit h 6 m mbol t an d clean .
O-RING SReplace . CYLINDE
R HEA D ORIFIC E
Remove wit h 6m mbolt an d clean .
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