radiator cap ACURA NSX 1991 Service Repair Manual

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
(cont'd)ProCarManuals.com

Cooling
Illustrated Index
Syste m is unde r hig h pressur e whe n th e
engin e i s hot . T o avoi d dange r o f releasin g scaldin g
engin e coolant , remov e th e ca p onl y whe n th e engin e i s
cool .
Tota l Coolin g Syste m Capacity : Includin g expansio n
tank 2. 1 (2. 2 U S qt . 1. 8 Im p qt )
5 M/T : 16. 0 (17. 0 US qt , 14. 1 Imp qt )
4 A/T : 16. 5 (17. 4 US qt , 14. 5 Imp qt )
NOTE :
• Chec k al l coolin g syste m hose s fo r damage ,
leak s o r deterioratio n an d replac e i f necessary .
• Chec k al l hos e clamp s an d retighte n i f
necessary .
• Us e ne w O-ring s whe n reassembling .
Radiator, Wate r Pipe s an d Hoses :
BLEED BOL T10 N- m (1. 0 kg-m ,7 Ib-ft )
WASHE RReplace .
HEATER PIP E
RADIATO R
LOWE R HOS E
RADIATO R
UPPE R HOS E
RADIATO REngine coolan t refillin g an dbleeding , pag e 10- 5Leak test , pag e 10- 8Inspec t soldere d joint s an dseam s fo r leaks .Blow ou t dir t fro m betwee ncore fin s wit h compresse d air .If insects , etc. , ar e cloggin gradiator, was h the m of f wit hlow-pressur e water . BLEE
D PLU G
RESISTO R
RADIATO R DRAI N
PLU G
FRON T LOWE R
WATE R PIP E
FRON T UPPE R
WATE R PIP E FA
N SHROU D
5 x 0. 8 m m4.5 N- m (0.4 5 kg-m , 3. 3 Ib-ft )
Replace .
BLEED BOL T
10 N- m (1. 0 kg-m ,7 Ib-ft )
WASHER S
Replace .
WATER PIP E
DRAI N BOLT S
15 N- m (1. 5 kg-m , 1 1 Ib-ft )
WATE RPIPE ASSEMBL YWASHE
RReplace .
FAN MOTO R
ProCarManuals.com

Engine Coolant Refilling and Bleeding

CAUTION: When pouring engine coolant, be sure to

shut the relay box lid and not let coolant spill on the

electrical parts or the paint. If any coolant spills, rinse it

off immediately.

NOTE:

• Perform this maintenance when the engine is cool.

• Before replacing the coolant, turn the ignition ON,

slowly turn the climate control temperature knob to

90° and turn off the ignition. This will allow the

coolant in the heater to drain out with the rest of the

system.
1. Open the hood, the rear window and the engine

cover.

2. Remove the cover protecting the water pipes and

shift cables on the underside of the car.

3. Before removing the expansion tank cap, first

loosen the cap to lower pressure.

CAUTION: Do not remove the expansion tank cap

when engine is hot. The coolant is under pressure

and may blow out and scald you. Open the cap

slowly when the engine is cool.

4. Loosen the drain plug in the bottom of the radiator,

and drain the coolant.

5. Remove the two drain bolts from the water pipes,

and drain the coolant.

WASHERS

Replace.

DRAIN BOLTS

15 N-m (1.5 kg-m, 11 Ib-ft)
DRAIN HOLE
DRAIN PLUGProCarManuals.com

Radiator
Engine Coolan t Refillin g an d Bleedin g
6. Instal l rubbe r hose s o n th e drai n bolt s a t th e fron t
an d rea r of the engin e unde r th e cylinde r banks .
Loose n th e drai n bolt s t o drai n th e coolant .
• Drainin g ca n b e don e mor e quickl y i f al l th e blee d
bolt s an d plu g ar e als o opened . Befor e openin g
them , mak e sur e th e coolan t leve l i n th e expan -
sio n tan k ha s com e dow n completel y s o tha t th e
coolan t wil l no t pou r ou t o f th e blee d bolt s an d
plug .
7. Whe n th e coolan t stop s draining , tighte n th e
radiato r drai n plug , wate r pip e drai n bolt s an d
engin e drai n bolts .
• B e sur e t o replac e th e wate r pip e drai n bol t
washer s wit h ne w ones .
REAR ENGIN E DRAI N BOL T
3 0 N- m (3. 0 kg-m , 2 2 Ib-ft )
8. Ope n al l fou r bleeders .
1 ) Loose n th e radiato r blee d plug .
2 ) Remov e th e heate r pip e blee d bolt .
3 ) Loose n th e wate r pip e blee d bolt .
4 ) Loose n th e engin e blee d bol t o n th e therm o
cover.
9. Mi x th e recommende d antifreeze/coolan t wit h a n
equa l amoun t o f wate r i n a clea n container .
NOTE:
• Us e onl y Honda-recommende d anti-freeze /
coolant.
• Fo r bes t corrosio n protection , th e coolan t con -
centration s mus t b e maintaine d year-roun d a t
50 % minimum . Coolan t concentration s les s tha n
50 % ma y no t provid e sufficien t protectio n
agains t corrosio n o r freezing .
• Coolan t concentration s greate r tha n 60 % wil l
impai r coolin g efficienc y an d ar e no t recom -
mended.
CAUTION :
• D o no t mi x differen t brand s o f anti -
freeze/coolant .
• D o no t us e additiona l rus t inhibitor s o r anti-rus t
products ; the y ma y no t b e compatibl e wit h th e
recommende d coolant .
Engin e Coolan t Refil l Capacity : Includin g expansio n
tank 2. 1 (2. 2 U S qt , 1. 8 Im p qt )
Manual : 12. 0 (12. 7 U S qt , 10. 6 Im p qt )
Automatic : 12. 0 (12. 7 U S qt , 10. 6 Im p qt )
FRON T ENGIN E DRAI N BOL T30 N- m (3. 0 kg-m , 2 2 Ib-ft )
ProCarManuals.com

Heater-Evaporator Unit

Replacement

SRS components are located in this area. Review the SRS
component locations, precautions, and procedures in the
SRS section (24) before performing repairs or service.
1.
Remove
the
blower
unit
(see
page
22-67 ('93-'96),
63('91-'92)).

2. When the engine is cool, drain the engine coolant from the radiator (see section 10).
Do not remove the radiator cap when

the engine is hot; the engine coolant is under

pressure and could severely scald you.

CAUTION: Engine coolant will damage paint. Quick-

ly rinse any spilled engine coolant off painted sur-

faces.
3. Disconnect the heater valve cable from the heater valve.

4.
Disconnect
the
heater hoses. Engine cootant
will
run out when the hoses are disconnected, drain it
into a clean drip pan.

HEATER

VALVE CASLE
HEATER VALVE
5. Recover the refrigerant from the A/C system with a
R-134a refrigerant Recovery/Recycling/Charging
System. (see page 22-73).
6. Disconnect the receiver line and the suction line from the evaporator. Cap the open fittings immediately
to keep moisture out of the system.

RECEIVER LINE

New parts (R-134a)

SECTION LINE

7. Remove the dashboard (see section 20).
8. Remove the heater duct. 9. Remove the four mounting bolts, disconnect the con-
nectors from the control units and the evaporator

temperature sensor connector from the control unit

bracket, then remove the control unit bracket.
*: CORROSION RESISTANT BOLT
EVAPORATOR

TEMPERATURE
SENSOR CONNECTOR
CONTROL

UNIT

BRACKET
SRS MAIN

HARNESS

* 6 x 1,0 mm
10 N·m
(1.0 kg-m,
7 Ib-ft)

* 6 x 1.0 mm
10 N·m (1.0 kg-m, 7 Ib-ft)
10. Remove the woofer enclosure (see section 23).ProCarManuals.com

Warning/Caution Label Locations

SRS CAUTION LABELS: Refer to page 1-8.
FROZEN

BATTERY CAUTION

BATTERY

CAUTION

RADIATOR BLEED

PLUG CAUTION
AIR CONDITIONING
R-134a CAUTION (U.S.A only)
EXPANSION
TANK CAP

CAUTION

ENGINE COOLANT CAUTION PRECAUTION

SPARK PLUG

CAUTION

TIRE INFORMATION
ABS CAUTION

ABS and BRAKE

FLUID CAUTION

RETRACTABLE

HEADLIGHT CAUTION

EMISSION CONTROL

INFORMATION and

VACUUM HOSE

ROUTING DIAGRAM

(cont'd)ProCarManuals.com

Warning/Caution Label Locations

SRS CAUTION LABELS: Refer to page 1-8.
FROZEN

BATTERY CAUTION

BATTERY

CAUTION

RADIATOR BLEED

PLUG CAUTION
AIR CONDITIONING R-134a CAUTION(U.S.A only)

EXPANSION

TANK CAP CAUTION
ENGINE COOLANT
CAUTION • PRECAUTION
SPARK PLUG
CAUTION

TIRE INFORMATION
EMISSION CONTROL

INFORMATION and

VACUUM HOSE

ROUTING DIAGRAM
RETRACTABLE

HEADLIGHT CAUTION
ABS and BRAKE

FLUID CAUTION ABS CAUTION

(cont'd)ProCarManuals.com

Engine Removal/Installation

Make sure jacks and safety stands are placed proper-ly and hoist brackets are attached to the correct
positions on the engine (see section 1).
Make sure the car will not roll off stands and fall
while you are working under it. 3. Remove the expansion tank cap to speed draining.
Use care when removing the expan-
sion tank cap to avoid scalding by hot engine
coolant or steam.

4. Raise the hoist to full height.
5. Drain the engine coolant (see section 10).

STRUT BAR
10 x
1.25
mm

39 N.m (3.9 kg-m, 28 Ib-ft)
EXPANSION TANK

CAP

: CORROSION RESISTANT BOLT
(cont'dj

1. Move the seat bottoms and backs as far forward as

they will go.

2. Disconnect the battery negative terminal first, then
the positive terminal.
Loosen the drain plug from the radiator lower

tank.

Remove two drain bolts from the water pipes

Reinstall the drain bolts with new washers.

Loosen the front and rear engine drain bolts to
drain engine coolant from cylinder heads. Con-
nect rubber hoses to the drain bolts.
6. Drain transmission oil/fluid. Reinstall the drain plug using a new washer.
CAUTION: Do not overtighten the drain plug.
7. Drain the engine oil. Reinstall the drain plug using a new washer.
8. Lower the hoist.
9. Remove the strut bar.
CAUTION:
Use front and rear fender covers to avoid damaging
painted surfaces.
Unspecified items are common.Unplug the wiring connectors carefully while holding
the coupler and the connector portion to avoid damage.
Mark all wiring and hoses to avoid mis-connection.
Also, be sure that they do not contact other wiring or hoses or interfere with other parts.
If the ground clearance needs to be increased, use a
scissors jack and install the rubber spacers to the coil
springs (page 1-8).
Put rubber pads under the jacking points when using
jacks or safety stands to avoid damaging the body (page 1-9 to 11).ProCarManuals.com

Label Locations

SRS CAUTION LABELS: Refer to page 1-6.
BATTERY CAUTION ALB CAUTION

ALB and BRAKE
FLUID CAUTION
COOLING FAN

CAUTION

RADIATOR BLEED

PLUG CAUTION
AIR CONDITIONER
CAUTION
RETRACTABLE

HEADLIGHT CAUTION
FAN CAUTION

EXPANSION

TANK CAP

CAUTION

COOLANT
CAUTION PRECAUTION
EMISSION CONTROL
INFORMATION and
VACUUM HOSE
ROUTING DIAGRAM

SPARK PLUG

CAUTION
TIRE INFORMATIONProCarManuals.com

Label Locations

SRS CAUTION LABELS: Refer to page 1-14.
BATTERY CAUTION
COOLING FAN
CAUTION

RADIATOR BLEED

PLUG CAUTION
AIR CONDITIONER
CAUTION
EXPANSION
TANK CAP
CAUTION

COOLANT

CAUTION • PRECAUTION

SPARK PLUG

CAUTION

TIRE INFORMATION
EMISSION CONTROL

INFORMATION and

VACUUM HOSE
ROUTING DIAGRAM
FAN CAUTION

RETRACTABLE

HEADLIGHT CAUTION
ALB and BRAKE

FLUID CAUTION ALB CAUTIONProCarManuals.com