LEXUS SC400 1991 Service Repair Manual

16. INSTALL TIMING BELT TENSIONER(a) Temporarily install the tensioner with the two bolts.
(b) Alternately tighten the two bolts.
Torque: 26 N Vm (270 kgf Vcm, 20 ft Vlbf)
(c) Using pliers, remove the 1.27 mm hexagon wrench from
the tensioner.
17. CHECK VALVE TIMING (a) Turn the crankshaft pulley two revolutions from TDC toTDC.
NOTICE: Always turn the crankshaft clockwise.
(b) Check that each pulley aligns with the timing marks as shown in the figure.
If the marks do not align, remove the timing belt and reinstall
it.
18. INSTALL SPARK PLUGS Using a 16 mm plug wrench, install the eight spark plugs.
Torque: 18 N Vm (180 kgf Vcm, 13 ft Vlbf)
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19. INSTALL DRIVE BELT TENSIONERInstall the tensioner with the bolt and two nuts.
Torque: 16 N Vm (160 kgf Vcm, 12 ft Vlbf)
HINT: Use bolt 106 mm (4.17 in.) in length.
20. INSTALL ALTERNATOR (a) Install the alternator and A/T oil cooler pipe bracket withthe bolt and nut.
Torque: 37 N Vm (380 kgf Vcm, 27 ft Vlbf)
(b) Connect the alternator connector.
(c) Connect the alternator wire with the nut and cap.
21. INSTALL RH DISTRIBUTOR HOUSING (a) Install the distributor housing with the three bolts.
Torque: 18 N Vm (185 kgf Vcm, 13 ft Vlbf)
HINT:
w The RH distributor housing is marked with ºRº.
w Each bolt length is indicated in the illustration.
Bolt length: A 38 mm (1.50 in.)
B 96 mm (3.78 in.)
(b) Connect the cam position sensor connector.
22. INSTALL LH DISTRIBUTOR HOUSING (a) Install the distributor housing with the three bolts.
Torque: 18 N Vm (185 kgf Vcm, 13 ft Vlbf)
HINT:
w The LH distributor housing is marked with ºLº.
w Each bolt length is indicated in the illustration.
Bolt length: A 38 mm (1.50 in.)
B 80 mm (3.15 in.)
23. INSTALL DISTRIBUTOR ROTORS (a) Align the protrusion of the distributor rotor with thegroove of the camshaft timing pulley.
(b) Install the distributor rotor with the two bolts. Install the two distributor rotors.
Torque: 3.8 N Vm (39 kgf Vcm, 34 in. Vlbf)
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24. INSTALL DISTRIBUTOR CAPSInstall the distributor cap with the three bolts. Install the two
distributor caps.
Torque: 3.8 N Vm (39 kgf Vcm, 34 in. Vlbf)
25. INSTALL RH NO.2 TIMING BELT COVER
(a) Install the four gaskets to the timing belt cover.
(b) Install the connector grommet to the timing belt cover.
(c) Install the timing belt cover with the five bolts.
Torque (12 mm head bolt):
16 NVm (160 kgf Vcm, 12 ft Vlbf)
HINT (12 mm head bolt): Use bolts 106 mm (4.17 in.) in
length.
(d) Install the wire clamp to the timing belt cover.
(e) Install the cam position sensor connector to the ignition
coil bracket.
26. INSTALL LH NO.2 TIMING BELT COVER (a) Install the two gaskets to the timing belt cover.
(b) Run the cam po sition sensor wire through the timing belt
cover hole.
(c) Install the timing belt cover and connector bracket with the three bolts.
(d) Connect the cam position sensor connector.
(e) Install cam position sensor c onnector to connector
bracket.
(f) Install the connector grommet to the timing belt cover hole.
27. INSTALL DRIVE BELT IDLER PULLEY Install the idler pulley and cover plate with the pulley bolt.
Torque: 37 N Vm (380 kgf Vcm, 27 ft Vlbf)
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28. INSTALL HIGH±TENSION CORDS, HIGH±TENSIONCORD CLAMP AND LOWER HIGH±TENSION CORD
COVER ASSEMBLY
(a) Install the lower high±tension cord cover with the bolt.
(b) Connect the high±tension cord to RH ignition coil.
(c) Connect the four high±tension cord to the RH sparkplugs.
(d) Install the RH rear and front high±tension cord clamps
with the two bolts.
HINT: Place the front and rear ends of the front hightension
cord clamp on the rear high±tension cord clamp and lower
high±tension cord cover.
(e) Connect the four high±tension cord to the LH spark plugs.
(f) Install the LH rear and front high±tension cord clamps
with the two bolts.
HINT: Place the front and rear ends of the front hightension
cord clamp on the rear high±tension cord clamp and lower
high±tension cord cover.
(g) Fit the high±tension cords to the high±tension cord clamp. (See page IG±16)
29. INSTALL RH NO.3 TIMING BELT COVER (a) Install the three gaskets to the timing belt cover.
(b) Fit portion A of the timing belt cover, matching it with the
lower high±tension cord cover.
(c) Install the timing belt cover with the three bolts.
30. INSTALL VSV FOR EVAP SYSTEM Install the VSV with the two bolts.
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31. INSTALL LH NO.3 TIMING BELT COVER(a) Install the three gaskets to the timing belt cover.
(b) Install the cord grommet to the high±tension cord.
(c) Install the cord grommet to the timing belt cover.
(d) Fit portion A of the timing belt cover, matching it with the
lower high±tension cord cover.
(e) Install the timing belt cover with the four bolts.
32. INSTALL RH ENGINE WIRE COVER (a) Fit portions A and B of the engine wire cover, matchingthem with the lower high±tension cord cover and No. 3
timing belt cover.
(b) Install the engine wire cover with the bolt.
33. INSTALL LH ENGINE WIRE COVER (a) Connect portions A and B of the engine wire cover to the
wire cover brackets.
(b) Set the VSV (for Fuel pressure control system) wire in original position.
(c) Fit portions C and D of the engine wire cover, matching them with the lower high±tension cord cover and No.3
timing belt cover.
(b) Install the engine wire cover with the two bolts.
34. INSTALL UPPER HIGH±TENSION CORD COVER (a) Fit portion A of the upper high±tension cover, matchingit with the top of the lower high±tension cord cover.
(b) Push the front side of the high±tension cord cover, and connect the front side claw groove of the upper
high±tension cord cover to the claw of the lower
high±tension cord cover.
(c) Install the upper high±tension cord cover with the two bolts.
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35. INSTALL LH IGNITION COIL(a) Install the ignition coil with the two bolts.
(b) Connect the following connectors and cord:(1) Ignition coil connector
(2) Noise filter connector
(3) High±tension cord
36. INSTALL INTAKE AIR CONNECTOR (a) Connect the end portions of the intake air connector tothe throttle body and air cleaner hose.
(b) Tighten the two hose clamps.
(c) Install the bolt holding the intake air connector to the cylinder head cover.
(d) Connect the following hoses: (1) Air hose to ISC valve
(2) Air hose (from PS air control valve) to intake air connector
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37. INSTALL A/C COMPRESSOR(a) In sta ll th e A/C co mp re sso r, co mp re sso r sta y an dground cable with the three bolts and nut.
Torque: Bolt 49 N Vm (500 kgf Vcm, 36 ft Vlbf)
Nut 29 N Vm (300 kgf Vcm, 22 ft Vlbf)
(b) Connect the A/C compressor connector.
38. INSTALL RADIATOR AND RESERVOIR TANK (See steps 25 and 26 on pages EM±174 to 175)
39. INSTALL DRIVE BELT Install the drive belt by turning the drive belt tensioner coun-
terclockwise.
HINT: The pully bolt for the belt tensioner has a lefthand
thread.
40. INSTALL BATTERY
41. FILL WITH ENGINE COOLANT (See page CO±7)
42. CHECK IGNITION TIMING (See page IG±28)
Ignition timing:
8±125 BTDC @ idle
(w/ Terminals TE1 and E1 connected)
43. INSTALL ENGINE UNDER COVER
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CYLINDER HEADS
COMPONENTS FOR REMOVAL AND
INSTALLATION
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COMPONENTS FOR REMOVAL AND
INSTALLATION (Cont'd)
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REMOVAL OF CYLINDER HEADS
(See Components on pages EM±58 and 59)
1. DISCONNECT TIMING BELT FROM CAMSHAFT TIMING PULLEYS
(See steps 1 to 28 on pages EM±35 to 42)
2. REMOVE CAMSHAFT TIMING PULLEYS AND HYDRAULIC PUMP
(See steps 29 and 31 on pages EM±42 and 43)
HINT:
w Be careful not to drop anything inside the timing belt
cover.
w Do not allow the timing belt to come into contact with oil,
water or dust.
3. DISCONNECT PS PUMP FROM LH CYLINDER HEAD (a) Disc onnect the vacuum hose from the air intake
chamber.
(b) Remove the three bolts and nut, and disconnect the PS pump.
HINT: Put aside the PS pump, and suspend it.
4. REMOVE CATALYTIC CONVERTERS (MAIN) (a) Remove the four bolts holding the pipe support bracketto the transmission.
(b) Remove the four bolts and nuts holding the catalytic converters to the front exhaust pipe. Remove the pipe
support bracket.
(c) Disconnect the front exhaust pipe from the catalytic
converter, and remove the two gaskets.
(d) Remove the three nuts, catalytic converter and gasket. Remove the two catalytic converters.
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