ACURA NSX 1991 Service Repair Manual

Piston Ring s
Ring-to-Groov e Clearance s
After installin g a ne w se t o f rings , measur e ring-to-groov e
clearances:
Top an d Secon d Rin g Clearanc e
Standar d (New) :
0.030-0.05 5 mm
(0.00 1 - 0.00 2 in )
Servic e Limit : 0.1 3 m m (0.00 5 in )
FEELE R GAUG E
Alignmen t
1. Instal l th e ring s a s show n o n pag e 7- 15.
Identif y to p an d secon d ring s b y th e chamfe r o n th e
edge , an d mak e sur e the y ar e i n th e prope r groove s
i n th e piston .
NOTE : Th e manufacturin g mark s mus t b e facin g
upward .
2. Rotat e th e ring s i n thei r groove s t o mak e sur e the y
do no t bind .
MAR K
TO P RIN G
SECON D RIN G
OI L RIN G MAR
K
- SPACE R
3. Positio n th e rin g en d gap s a s shown :
SECON D RIN G CA PDO NO T positio n an y rin g ga pat pisto n thrus t surfaces .
TOP RIN G GA P
DO NO T positio n an y rin g ga pin lin e wit h pisto n pi n hole .OIL RIN G GA P
SPACE
R GA P
OI
L RIN G
GAP
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Piston/Connecting Ro d Assemblie s
Installation
Before installin g th e piston , appl y a coa t o f
engin e oi l t o th e rin g groove s an d cylinde r
bores.
1. I f th e crankshaf t i s alread y installed :
• Guid e th e pisto n carefull y t o preven t damage .
• Fi t lon g rubbe r hose s (abou t 3 0 c m (1 2 in ) long ) t o
th e connectin g ro d bolt s t o protec t th e crankshaft .
• Instal l th e piston s afte r settin g th e crankshaf t t o
BD C fo r eac h cylinder .
CORREC TINCORREC T
RUBBER HOSE S
Install th e pisto n assemblie s i n No . 1 an d No . 4
cylinders , No . 2 an d No . 5 cylinders , an d No . 3
an d No . 6 cylinders .
Instal l th e rin g compressor , chec k tha t th e bear -
in g i s securel y i n place ; the n positio n th e pisto n
i n th e cylinde r an d ta p i t i n usin g th e woode n
handl e of a hammer .
Sto p afte r th e rin g compresso r pop s fre e an d
chec k th e connectin g rod-to-cran k journa l align -
ment befor e puttin g ro d int o place .
Install th e ro d cap s wit h bearings , an d torqu e th e
nut s t o 2 0 N- m (2. 0 kg-m , 1 4 Ib-ft) , the n tur n th e
nu t 9 5 degree s (se e pag e 7-19 ).
If th e crankshaf t i s no t installed :
• Remov e th e ro d cap s an d bearings , instal l th e
ring compressor , the n positio n th e pisto n in th e
cylinde r an d ta p it i n usin g th e woode n handl e of
a hammer .
The arro w mus t fac ethe timin g bel t sid eof th e engin e an d th econnectin g ro d oi l hol emus t fac e th e rea r sid eof th e engine .
CONNECTIN G RO DOIL HOL E
NOTE : Maintai n downwar d forc e o n th e rin g com -
presso r t o preven t ring s fro m expandin g befor e
enterin g th e cylinde r bore .
Use th e woode n handl eof a hamme r t o push , o rtap th e pisto n int o th ecylinde r bore .
RING COMPRESSO R
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Crankshaft

Installation

Before installing the crankshaft, apply a coat of

engine oil to the main bearings and rod

bearings.

1. Insert bearing halves in the engine block and con-

necting rods.

2. Lower the crankshaft into the block.

3. Install the thrust washers on the No. 3 journal. Oil

thrust washer surfaces.

4. Install the bearings and caps. Tighten 9 x 1.25 mm

cap bolts to the specified torque.ProCarManuals.com

NOTE:
• Guid e th e pisto n carefull y t o preven t damage .
• Fi t lon g rubbe r hose s (abou t 3 0 c m long ) t o con -
nectin g ro d bolt s t o protec t th e crankshaft .
• Instal l th e piston s afte r settin g th e crankshaf t t o
BD C fo r eac h cylinder .
CORREC TINCORREC T
RUBBER HOSE S
9 x 0.7 5 mm20 N- m (2. 0 kg-m , 1 4 Ib-ft )
afte r tur n t o 95 °
MAR K
• Lin e u p th e mark s whe n installin g connectin g
rod cap .
5. Chec k th e ro d bearin g clearanc e wit h plastigag e
(se e pag e 7-7 ), the n torqu e th e connectin g ro d ca p
nuts .
NOTE : Referenc e number s o n connectin g rod s ar e
fo r big-en d bor e toleranc e an d d o NO T indicat e th e
positio n o f pisto n i n engine .
CONNECTIN G RO D CA P NU T TORQUIN G
METHOD
1) Torqu e th e connectin g ro d ca p nu t t o 2 0 N- m
(2. 0 kg-m , 1 4 Ib-ft ) wit h a beam-typ e torqu e
wrench .
2 ) Instal l a torqu e angl e gaug e t o th e ca p nut , the n
tur n th e ca p nu t 9 5 degrees .
Snap-onTA360 o requivalen t
BEARIN
G CA P
WASHERS
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Crankshaft
Installation
6. Instal l th e bearin g ca p bridge , an d tighte n 1 1 x 1. 5
m m bolt s t o th e specifie d torqu e diagonall y out -
war d fro m th e center .
Torqu e 6 6 N- m (6. 6 kg-m , 4 8 Ib-ft )
7 . Tighte n ca p sid e bolt s (1 0 x 1.2 5 mm ) t o th e
specifie d torque .
Torque : 5 0 N- m (5. 0 kg-m , 3 6 Ib-ft )
• Coa t th e bol t threa d an d sea t surfac e wit h
engin e oil .
NOTE : Th e shorte r sid e bolt s ar e fo r th e fron t side .
BEARIN G CA PBRIDG ECAP BRIDG E BOL T11 x 1. 5 m m66 N- m (6. 6 kg-m ,48 Ib-ft )
SID E BOL T
10 x 1.2 5 mm50 N- m (5. 0 kg-m ,36 Ib-ft ) CA
P BOL T9 x 1.2 5 mm40 N- m (4. 0 kg-m ,29 Ib-ft )
8. Appl y liqui d gaske t t o th e bloc k matin g surfac e o f
the lef t sid e cove r an d oi l pum p case , an d instal l
them o n th e engin e block .
NOTE : Th e sea l surfac e o n th e bloc k shoul d b e
dry . Appl y a ligh t coa t o f oi l t o th e crankshaf t an d
to th e li p o f seal .
LEF T SIDE :
Apply liqui dgaske t t o bloc kmatin g surface .
LEFT SID E COVE R
SPECIA L BOLT S
6 x 1. 0 m m12 N- m (1. 2 kg-m ,9 Ib-ft )
Replace . DOWE
L PI N
BEARIN G CA P BOLT S TORQU E SEQUENC E
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6 x 1. 0 m m12 N- m (1. 2 kg-m ,9 Ib-ft )
OIL PUM P
Appl y liqui d
gaske t t o bloc kmatin g surfaces .
SPECIAL BOLT S6 x 1. 0 m m12 N- m (1. 2 kg-m ,9 Ib-ft )Replace .
SPECIAL BOLT S8 x 1.2 5 mm22 N- m (2. 2 kg-m ,16 Ib-ft )Replace .
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
dry befor e applyin g liqui d gasket .
• Appl y liqui d gaske t evenly , bein g carefu l t o cove r
al l o f 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 .
LEFTSIDE COVE R
Apply liqui d gaske talong th e broke n line .
OIL PUM PApply liqui d gaske talong th e broke n line .
• D o no t instal l th e part s i f fiv e minute s o r mor e
have elapse d sinc e applyin g liqui d gasket .
Instead reappl y liqui d gaske t afte r removin g ol d
residue .
• Afte r assembly , wai t a t leas t 2 0 minute s befor e
filling th e engin e wit h oil .
9. Instal l th e oi l pas s pip e an d joint .
10 . Instal l th e baffl e plate .
11 . Instal l th e oi l screen .
12 . Instal l th e oi l pa n (se e pag e 8-10 ).
CAUTION : Wheneve r an y crankshaf t o r connec -
tin g ro d bearin g i s replaced , afte r reassembly , ru n
th e engin e a t idlin g spee d unti l i t reache s norma l
operatin g temperature , the n continu e t o ru n fo r ap -
proximatel y 1 5 minutes .
OIL PUM P SIDE :
6 x 1. 0 m m12 N- m (1. 2 kg-m , 9 Ib-ft )
OIL SCREE NBAFFLE PLAT E
OIL PAS SPIPE
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Special Tool s
8-9
8-5
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Engine Lubricatio n
Illustrated Inde x
FRON T CYLINDE RHEADENGIN E OI L PRESSUR E GAUG ESENDIN G UNI T22 N- m (2. 2 kg-m . 1 6 Ib-ft )
NOTE :
• Us e ne w O-ring s whe n reassembling .
• Appl y oi l t o O-ring s befor e installation .
• Us e liqui d gasket , Par t No . 08718-0001 .
• I f th e botto m o f th e oi l pa n is deformed , i t shoul d b e
repaire d o r th e oi l pa n shoul d b e replace d t o retai n
prope r clearanc e betwee n th e scree n an d th e
bottom .
OIL CONTRO L ORIFIC ERemove wit h 6 m mbol t an d clean .
O-RIN GReplace .
8 x 1.2 5 mm22 N- m (2. 2 kg- m16 Ib-ft )Replace .
ENGINE OI LPRESSUR ESWITCH
OIL FILTE R BAS EIllustrate d Index ,page 8-1 2
OIL PUM PIllustrate d index , pag e 8- 7Inspection , pag e 8 -8Appl y liqui d gaske t t omatin g surfac e o f engin e block .
OIL PA N GASKE T
Replace .
OIL PA N• D o no t defor mthe bottom .Refer t o pag e 8-1 0whe n installing .
OIL FILTE ROne tur n o r22 N- m (2. 2 kg-m ,16 Ib-ft )Replacemen t 8- 5
6 x 1. 0 m m12 N- m(1.2 kg-m , 9 Ib-ft )
6 x 1. 0 m m12 N- m(1.2 kg-m , 9 Ib-ft )
DRAI N PLU G
20 x 1. 5 m m45 N- m (4. 5 kg-m , 3 3 Ib-ft )
6 x 1. 0 m m14 N- m (1. 4 kg-m , 1 0 Ib-ft )
ENGIN E OI LCOOLE R
WATE
R PAS S PIP E
DOWEL PIN S
SPECIA L BOLT S
8 x 1.2 5 mm22 N- m (2. 2 kg-m ,16 Ib-ft ) O-RING S
Replace . Replace .
OI L PAS S
PIPE
SPECIA L BOLT S6 x 1. 0 m m12 N- m(1.2 kg-m , 9 Ib-ft )
Replace .
6 x 1. 0 m m12 N- m (1. 2 kg-m , 9 Ib-ft )
DOWE
L PI N O-RING
S
Replace .
8 x 1.2 5 mm12 N- m (2. 2 kg-m ,16 Ib-ft )
OILSCREE N
WASHE R
Replace .
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Engine Oil

Inspection

1. Check engine oil with the engine off and the car

parked on level ground.

2. Make certain that the oil level indicated on the

dipstick is between the upper and lower marks.

3. If the level has dropped close to the lower mark,

add oil until it reaches the upper mark.

CAUTION: Insert the dipstick carefully to avoid

bending it.ProCarManuals.com

Oil Filte r
Replacemen t
CAUTION: Loose n th e oi l filte r carefull y whil e th e
engin e is hot , th e ho t oi l ma y caus e scalding .
1 . Remov e th e oi l filte r wit h th e specia l too l a s shown .
2 . Inspec t th e thread s an d rubbe r sea l o n th e ne w filter .
Wip e of f th e sea t o n oi l filte r base , the n appl y a ligh t
coa t o f oi l t o th e rubbe r sea l an d instal l th e filter .
3 . Afte r th e rubbe r sea l i s seate d agains t th e base ,
tighte n th e oi l filte r b y turnin g i t approximatel y on e
turn .
Torque : On e tur n (2 2 N- m (2. 2 kg-m , 1 6 lb-ft)) .
OIL FILTE R WRENC H
0791 2-611000 1
Torque : On e tur n
(2 2 N- m (2. 2 kg-m , 1 6 lb-ft) )
4. Star t th e engine , an d chec k th e filte r fo r oi l leakage .
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