engine ACURA NSX 1997 Service Manual PDF

5. Instal l th e sid e engin e mount , the n tighte n th e bolt s
in th e numbere d sequenc e a s show n
Engine Removal/Installatio n
Installation (cont'd )
7. Tighte n th e rea r moun t mountin g bolt .
• Chec k tha t th e sprin g cli p o n th e en d o f eac h
driveshaf t click s int o place .
CAUTION : Us e ne w sprin g clips .
• Blee d ai r fro m th e coolin g syste m (se e pag e 10-5 ).
• Blee d ai r fro m th e brak e line s (se e sectio n 19 ).
• Chec k th e clutc h peda l fre e pla y (se e sectio n 12 ).
• Adjus t th e clutc h guid e assemblie s whe n disas -
semblin g clutc h (se e sectio n 12 ).
• Chec k tha t th e transmissio n shift s int o gea r
smoothly .
• Adjus t th e alternato r bel t (se e sectio n 23 ).
• Adjus t th e A/ C compresso r bel t (se e sectio n 22 ).
• Clea n batter y post s an d cabl e terminal s wit h
sandpaper , assemble , the n appl y greas e t o pre -
ven t corrosion .
• Inspec t fo r fue l leakag e (se e sectio n 11 ).
• Afte r assemblin g th e fue l lin e parts , tur n o n
th e ignitio n switc h (d o no t operat e th e starter )
s o tha t th e fue l pum p operate s fo r approxi -
matel y tw o second s an d th e fue l lin e pressu -
rizes . Repea t thi s operatio n tw o o r thre e time s
an d chec k fo r fue l leakag e a t an y poin t i n th e
fue l line .
• Chec k an d adjus t whee l alignmen t (se e sectio n 18 ).
• Refil l th e engin e wit h engin e oi l (se e pag e 8-4 ).
• Refil l th e transmissio n wit h oil/flui d (se e
section 1 3 o r section 14 ).
6 . Tighte n th e transmissio n moun t mountin g bolt .
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VTEC

VTEC Solenoid Valve Inspection

1. Disconnect the 2P connector from the VTEC sole-

noid valve.

2. Measure resistance between the BLU/YEL (front/rear)

terminals and body ground.

BLU/YEL

3. If the resistance is within specifications, remove the

VTEC solenoid valve from the cylinder head, and

check the VTEC solenoid valve filter for clogging.

• If there is clogging, replace the engine oil filter

and engine oil.

VTEC SOLENOID VALVE

VTEC SOLENOID VALVE

FILTER/O-RING

Replace.
4. If the filter is not clogged, push the VTEC solenoid

valve with your finger and check its movement.

• If VTEC solenoid valve is normal, check the engine

oil pressure.ProCarManuals.com

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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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
Remova l
Engine remova l i s no t require d fo r thi s procedure .
Mak e 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 cor -
rec t position s o n th e engine .
CAUTION :
• Us e a fende r cove r (specia l tool ) t o avoi d damagin g
painte d surfaces .
• Unplu g th e wirin g connector s carefull y whil e holdin g
the connecto r portio n to avoi d damage .
• T o avoi d damagin g th e cylinde r heads , wai t unti l th e
engin e coolan t temperatur e drop s belo w 100° F
(3 8° C) befor e loosenin g th e retainin g bolts .
• D o no t ope n th e engin e cove r whe n th e roo f pane l i s
store d (NSX- T ope n top) .
NOTE :
• Unspecifie d item s ar e common .
• 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 .
• Inspec t th e timin g bel t befor e removin g th e cylinde r
head .
• Tur n th e crankshaf t pulle y 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 . Disconnec t th e negativ e termina l fro m th e battery .
2 . Remov e th e expansio n tan k cap .
Us e car e whe n removin g th e expan -
sio n tan k ca p t o avoi d scaldin g b y engin e coolan t
o r steam .
3 . Rais e th e car , the n remov e th e righ t rea r wheel/tire .
4 . Drai n th e engine coolan t (se e pag e 10-5 ). 5
. Remov e th e fron t exhaus t manifol d (M/T) .
-1 . Remov e th e cente r ro d assembl y an d unde r
guar d (se e pag e 5-7 ).
-2 . Remov e th e rea r bea m ro d assembl y (se e pag e
5-8).
-3 . Remov e th e fron t engin e mount , the n remov e
th e fron t bea m (se e pag e 5-8 ).
-4 . Remov e th e fron t mount .
FRONT ENGIN EMOUNT
-5. Disconnec t th e fron t primar y heate d oxyge n
senso r (fron t primar y HO2S ) connecto r an d
fron t secondar y heate d oxyge n senso r (fron t
secondar y HO2S ) connector , the n remov e th e
fron t exhaus t manifol d an d fron t thre e wa y cat -
alytic converte r (TWC ) assembly .
COVERGASKE TReplace .FRONT SECONDAR Y
HO2 S CONNECTO R
Replace.
FRONT EXHAUS T
MANIFOL D AN D
FRON T TW C
ASSEMBL Y FRON
T PRIMAR Y
HO2 S CONNECTO R
ProCarManuals.com

Cylinder Head s
Remova l (cont'd )
12. Remov e th e engin e cove r sta y fro m th e stru t brace ,
the n se t th e engine cover sta y betwee n th e engine
cove r an d rea r hatc h latc h (NSX- T ope n top) .
CAUTION : Us e a sho p towe l t o avoi d damagin g
painte d surfaces .
SHOPTOWE L
13. Reliev e fue l pressur e (se e sectio n 11 ).
D o no t smok e whil e workin g o n fue l
system ; kee p ope n flam e o r spar k awa y fro m wor k
area . Drai n fue l onl y int o a n approve d container .
14 . Remov e th e fue l fee d pip e an d fue l retur n hos e (se e
pag e 5-5 ).
15 . Remov e th e evaporativ e emissio n (EVAP ) contro l
caniste r hos e an d brak e booste r vacuu m hos e (se e
pag e 5-5 ).
16 . Disconnec t th e breathe r pip e an d vacuu m hose , the n
remov e th e ai r cleane r housing .
AIR CLEANE RHOUSING
BREATHE RPIPE
17. Remov e th e hoses , the n remov e th e expansio n tan k
(se e pag e 5-5 ).
18 . Remov e th e radiato r hose s an d heate r hos e (se e
pag e 5-6 ).
19 . Disconnec t th e tw o connectors , the n remov e th e
contro l bo x (se e pag e 5-6 ).
20 . Remov e th e intak e manifol d plat e an d to p cover .
INTAK E MANIFOL DPLATE
TO P COVE R
21. Remov e th e fue l injecto r covers .
FUEL INJECTO R
COVE R
ProCarManuals.com

Camshafts

Inspection

NOTE:

• Do not rotate the camshaft during inspection.

• Remove the rocker arms and rocker shafts.

1. Put the camshafts, the camshaft holders and holder

plates on the cylinder head, and then tighten the

bolts to the specified torque.

NOTE: Apply clean engine oil to 8 mm bolt threads.

Specified torque:

8 mm x 1.25 mm bolts:

22 N-m (2.2 kgf-m, 16 Ibf-ft)

6 mm x 1.0 mm bolts:

9.8 N-m (1.0 kgf-m, 7.2 Ibf-ft)

CAMSHAFT HOLDER BOLTS TORQUE

SEQUENCE
2. Seat the camshaft by pushing it toward the left end of

cylinder head.

3. Zero the dial indicator against the left end, then push

the camshaft back and forth, and read the end play.

Camshaft End Play:

Standard (New): 0.05 - 0.15 mm

(0.002 - 0.006 in)

Service Limit: 0.5 mm (0.02 in)

4. Remove the bolts, then remove the camshaft holders

from the cylinder head.

5. Lift the camshaft out of the cylinder head, wipe it

clean, then inspect the lift ramps. Replace the

camshaft if lobes are pitted, scored, or excessively

worn.

6. Clean the camshaft bearing surfaces in the cylin-

der head, then set the camshaft back in place.

7. Insert a plastigage strip across each journal.

8. Install the camshaft holders, and then tighten the

bolts to the specified torque as shown in the left

column on this page.

(cont'd)ProCarManuals.com

Cylinder Heads

Installation (cont'd)

Rear:

8 x
1.25
mm

22 N-m (2.2 kgf-m,

16 Ibf-ft)
REAR PRIMARY

HEATED OXYGEN SENSOR

(REAR PRIMARY HO2S)

44 N-m (4.5 kgf-m,

33 Ibf-ft)

Be careful not to damage.

GASKET

Replace.

REAR EXHAUST

MANIFOLD

EXHAUST

MANIFOLD

COVER

SELF-LOCKING NUT

8 x
1.25
mm

30 N-m (3.1 kgf-m,

22 Ibf-ft)

Replace.

3. Install the cylinder heads on the engine block.

The cylinder head dowel pins and the head oil con-

trol orifice must be aligned.

• Always use a new cylinder head gasket.

• Clean the oil control orifice before installing.

CYLINDER HEAD

GASKET

Replace.
OIL CONTROL

ORIFICES

Clean.
CYLINDER HEAD

GASKET

Replace.

DOWEL PIN
DOWEL

PINS

O-RING

Replace.
4. Tighten the cylinder head bolts sequentially in two

or three steps.

• Apply clean engine oil to the bolt threads and

washer contact surfaces.

Specified Torque

M/T:
11 x 1.5 mm

96 N-m (9.8 kgf-m, 71 Ibf ft)

A/T:
11 x 1.5 mm

76 N-m (7.8 kgf-m, 56 Ibf ft)

NOTE: We recommend using a beam-type torque

wrench. When using a preset-type torque wrench,

be sure to tighten slowly and not to over-tighten.

CYLINDER HEAD BOLTS TORQUE SEQUENCE

CYLINDER HEAD BOLT

M/T:
11 x 1.5 mm

96 N-m (9.8 kgf-m, 71 Ibf-ft)

A/T:
11 x 1.5 mm

76 N-m (7.8 kgf-m, 56 Ibf-ft)

Apply clean engine oil to the

bolt threads and washer contact

surfaces.ProCarManuals.com

Camshafts

Installation (cont'd)

5. Apply liquid gasket to the head mating surfaces of

the No. 1 and the No. 4 camshaft holders.

5. Apply liquid gasket to the shaded areas.

6. Install the camshaft holders.

NOTE:

• "F" or "R" marks are stamped on the camshaft

holders.

• The arrows must be pointing to the timing belt

side.

• Set two dowel pins in each camshaft holder.

FRONT:

No. 4 No. 3 No. 2 No. 1

CAMSHAFT CAMSHAFT CAMSHAFT CAMSHAFT

HOLDER HOLDER HOLDER HOLDER

No. 4 No. 3 No. 2 No. 1

CAMSHAFT CAMSHAFT CAMSHAFT CAMSHAFT

HOLDER HOLDER HOLDER HOLDER
7. Install the camshaft holder plates.

8. Tighten each bolt two turns at a time in the sequence

shown below to insure that the rockers do not bind

on the valves.

NOTE: Apply clean engine oil to 8 mm bolt threads.

Specified torque:

8 mm x 1.25 mm bolts:

22 N-m (2.2 kgf-m, 16 Ibf-ft)

6 mm x 1.0 mm bolts:

9.8 N-m (1.0 kgf-m, 7.2 Ibf-ft)

CAMSHAFT HOLDER BOLT TORQUE SEQUENCE

FRONT:ProCarManuals.com

Camshafts

Installation (cont'd)

17. Apply liquid gasket to the head cover gasket at the

eight corners of the recesses.

NOTE:

• Use liquid gasket, Part No. 08718 - 0001 or 08718

- 0003.

• Check that the mating surfaces are clean and dry

before applying liquid gasket.

• Do not install the parts if five minutes or more

have elapsed since applying liquid gasket. Instead,

reapply liquid gasket after removing old residue.

• After assembly, wait at least 20 minutes before

filling the engine with oil.

Apply liquid gasket to

the shaded areas.

18. When installing the cylinder head cover, hold the

head cover gasket in the groove by placing your fin-

gers on the camshaft contacting surfaces (top of the

semicircles).

Once the cylinder head cover is on the camshaft

holder, slide the cover slightly back and forth to

seat the head cover gasket.

NOTE:

• Before installing the cylinder head cover, clean

the cylinder head contacting surfaces with a

shop towel.

• Do not touch the parts where liquid gasket was

applied.

• Replace the washer when damaged or deterio-

rated.

CYLINDER

HEAD COVER
WASHER

6 x 1.0 mm

12 N-m (1.2 kgf-m,

8.7 Ibf-ft)
19. Tighten the nuts in two or three steps. In the final step,

tighten all nuts, in sequence, to 12 N-m (1.2 kgf-m,

8.7 Ibf-ft).

NOTE: After assembly, wait at least 20 minutes

before filling the engine with oil.

20. After installation, check that all tubes, hoses and

connectors are installed correctly.

NOTE: After installation, fill the engine with oil up to

the specified level, run the engine for more than three

minutes, then check for oil leakage.ProCarManuals.com