LEXUS SC400 1991 Service Repair Manual

(e) Check that the exhaust camshaft moves smoothly in the
thrust direction.
(f) Install the front bearing cap with the arrow mark facing forward.
HINT:
w Installing the front bearing cap will determine the thrust
position of the camshaft.
w Align the arrow marks at front and rear of the cylinder
head with the mark on the bearing cap.
(g) Install the other bearing caps in the sequence shown with the arrow mark facing forward.
HINT: Align the arrow marks at front and rear of the cylinder
head with the mark on the bearing cap.
(h) Apply a light coat of engine oil on the threads and under
the heads of the bearing cap bolts.
(i) Install the oil feed pipe and ten bolts.
HINT: Use bearing cap bolts 38 mm (1.50 in.) and 52 mm
(2.05 in.) in length. Use black colored 38 mm (1.50 in.) bolts.
Install the two 52 mm (2.05 in.) bolts in outside positions of
the oil pipe. Install the eight 38 mm (1.50 in.) bolts in the other
positions.
(j) Uniformly tighten the eight bearing cap bolts on the
bearing caps of the exhaust camshaft in several passes
in the sequence shown.
Torque: 16 N Vm (160 kgf Vcm, 12 ft Vlbf)
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(k) Alternately tighten the two bearing cap bolts on thebearing cap of the intake camshaft second from the front
in several passes.
Torque: 16 N Vm (160 kgf Vcm, 12 ft Vlbf)
(l) Bring the service bolt installed in the driven subgear
upward by turning the hexagon wrench head portion of
the camshaft with a wrench.
(m) Remove the service bolt.
8. CHECK AND ADJUST VALVE CLEARANCE (See steps 19 to 23 on pages EM±15 to 22)
Turn the camshaft, and position the cam lobe upward, check
and adjust the valve clearance.
Valve clearance:
Intake 0.15±0.25 mm (0.006±0.010 in.)
Exhaust 0.25±0.35 mm (0.010±0.014 in.)
9. INSTALL CAMSHAFT OIL SEALS(a) Apply MP grease to a new oil seal lip.
(b) Using SST and a hammer, tap in the two oil seals.
SST 09223±46011
10. INSTALL SEMI±CIRCULAR PLUGS (a) Remove any oil packing (FIPG) material.
(b) Apply seal packing to the semi±circular plug groove.
Seal packing: Part No. 08826±00080 or equivalent
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(c) Install the four semi±circular plugs.
11. INSTALL CYLINDER HEAD COVERS (a) Remove any oil packing (FIPG) material.
(b) Apply seal packing to the cylinder heads as shown in the
figure.
Seal packing: Part No.08826±00080 or equivalent
(c) Install the gasket to the cylinder head cover.
(d) Install the seal washer to the bolt. Install the cylinder head cover with the eight bolts. Uniformly tighten the
bolts. Install the two cylinder head covers
Torque: 5.9 N Vm (60 kgf Vcm, 52 in. Vlbf)
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12. INSTALL ENGINE HANGERSInstall the engine hanger with the two bolts.
Install the two engine hangers.
Torque: 37 N Vm (380 kgf Vcm, 27 ft Vlbf)
13. CONNECT GROUND STRAP TO RH CYLINDER HEAD
14. INSTALL ENGINE WIRE TO RH CYLINDER HEAD
Install the engine wire with the two bolts.
15. INSTALL ENGINE WIRE TO LH CYLINDER HEAD Install the engine wire with the five bolts.
16. INSTALL EGR PIPE TO RH EXHAUST MANIFOLD Install a new gasket and the EGR pipe with the two new nuts.
Torque: 18 N Vm (185 kgf Vcm, 13 ft Vlbf)
17. INSTALL OIL DIPSTICK AND GUIDE FOR ENGINE
(a) Install a new O±ring to the dipstick guide.
(b) Apply a light of engine oil on the O±ring.
(c) Push in the dipstick guide into the guide hole of the No.1
oil pan.
(d) Install the dipstick guide with the bolt.
(e) Install the oil dipstick.
18. INSTALL OIL DIPSTICK AND GUIDE FOR A/T
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19. INSTALL REAR WATER BY±PASS JOINT(a) Install two new gaskets and the water by±pass joint with
the four nuts. Alternately tighten the nuts.
Torque: 18 N Vm (185 kgf Vcm, 13 ft Vlbf)
(b) Install the bolt holding the water by±pass pipe to the
engine hanger.
20. INSTALL FRONT WATER BY±PASS JOINT (a) Install two new gaskets and the water by±pass joint with
the four nuts. Alternately tighten the nuts.
Torque: 18 N Vm (185 kgf Vcm, 13 ft Vlbf)
(b) Install the engine wire clamp with the bolt.
(c) Connect the following connectors:
(1) Water temperature sensor connector
(2) Cold start injector time switch connector
(3) Water temperature sender gauge connector
21. INSTALL INTAKE MANIFOLD (a) Place two new gaskets on the cylinder heads with thewhite painted mark facing upward.
NOTICE: Align the port holes of the gasket and cylinder
head. Be careful of the installation direction.
(b) Place the intake manifold in position on the cylinder head with the arrow mark facing forward.
NOTICE: Be careful of the installation direction.
(c) Install and uniformly tighten the six mounting bolts and
four mounting nuts.
Torque: 18 N Vm (185 kgf Vcm, 13 ft Vlbf)
HINT: Use bolts 30 mm (1.18 in.) in length.
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22. INSTALL DELIVERY PIPES AND INJECTORS(a) Install the grommet and a new O±ring to each injector.
(b) W h i l e t u r n i n g t h e I n j e c t o r c l o c k w i s e a n dcounterclockwise, push it to delivery pipe. Install the
eight injectors.
(c) Position the injector connector outward.
(d) Place the eight insulators and four spacers in positions on the intake manifold.
(e) P l a c e t h e e i g h t i n j e c t o r s a n d t w o d e l i v e r y p i p e s assembly in position on the intake manifold.
(f) Temporarily install the c onnector bracket and four
mounting nuts.
(g) Check that the injectors rotates smoothly.
(h) Position the injector connectors outward.
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(i) Tighten the four mounting nuts.
Torque: 18 NVm (185 kgf Vcm, 13 ft Vlbf)
23. INSTALL FUEL RETURN PIPE
(a) Temporarily install the return pipe with the bolt, two newgaskets and union bolt.
(b) Tighten the union bolt holding the return pipe to the fuel pressure regulator.
Torque: 35 N Vm (360 kgf Vcm, 26 ft Vlbf)
(c) Tighten the bolt holding the return pipe to the LH cylinder
head.
24. INSTALL ENGINE WIRE TO DELIVERY PIPES, REAR WATER BY±PASS JOINT AND RH CYLINDER HEAD
(a) Connect the eight injector connectors.
(b) Install the two engine wire connectors to connectorsbracket on the LH delivery pipe.
(c) Install the engine wire to the RH cylinder head with the two bolts.
(d) Install the engine wire to the rear water by±pass joint
with the two bolts.
(e) Install the engine wire to the delivery pipes with the four bolts.
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25. INSTALL ENGINE WIRE TO INTAKE MANIFOLDInstall the engine wire with the two bolts.
26. TEMPORARILY INSTALL EGR PIPE TO RH CYLINDER HEAD
Temporarily install a new gasket and the EGR pipe with the
two bolts.
HINT: Use bolt 25 mm (0.98 in.) in length.
27. CONNECT FUEL RETURN HOSE TO FUEL RETURN PIPE
28. CONNECT FUEL INLET HOSE TO LH DELIVERY PIPE Connect the inlet hose with two new gaskets and the pulsa-
tion damper.
SST 09612±24012 (09617±24011)
Torque: 39 N Vm (400 kgf Vcm, 29 ft Vlbf)
33 N Vm (340 kgf Vcm, 24 ft Vlbf) for SST
HINT: Use a torque wrench with a fulcrum length of 30 cm
(11.81 in.).
29. CONNECT HEATER WATER HOSES Connect the following hoses:(1) Water hose to water by±pass pipe
(2) Water hose to rear water by±pass joint
30. INSTALL AIR INTAKE CHAMBER (a) Install the cold start injector, tube and wire assemblywith the three bolts.
Torque: 7.8 N Vm (80 kgf Vcm, 69 in. Vlbf)
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(b) Place four new gaskets on the intake manifold.
HINT: Gaskets can only be used twice before being replaced.
(c) Place the air intake chamber on the intake manifold.
(d) Temporarily connect the EGR pipe to the air intakechamber with a new gasket and the two bolts.
HINT: Use bolts 20 mm (0.79 in.) in length.
(e) Temporarily install the air intake chamber and following
parts with the four bolts and eight nuts:
(1) VSV for fuel pressure control system
(2) (Exc. USA Spec.) VSV for EGR system
(3) A/T throttle cable bracket
(4) Check connector (ºDIAGNOSISº) connector
(f) Uniformly tighten the bolts and nuts in several passes.
Torque: 18 N Vm (185 kgf Vcm, 13 ft Vlbf)
HINT: Use bolts 40 mm (1.57 in.) in length.
(g) Tighten the two bolts holding the EGR pipe to the air
intake chamber.
Torque: 18 N Vm (185 kgf Vcm, 13 ft Vlbf)
(h) Tighten the two bolts holding the EGR pipe to the RH
cylinder head.
Torque: 18 N Vm (185 kgf Vcm, 13 ft Vlbf)
(i) Connect the cold start injector tube to the RH delivery
pipe with the two new gaskets and the union bolt.
Torque: 15 N Vm (150 kgf Vcm, 11 ft Vlbf)
(j) Connect the following connectors:
w Cold start injector connector
w SV connector for fuel pressure control system
w (Exc. USA Spec.)
VSV connector for EGR system
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31. INSTALL ACCELERATOR BRACKETInstall the bracket with the bolt and stud bolt.
32. INSTALL BRAKE BOOSTER UNION Install the union with two new gaskets and the union bolt.
Torque: 29 N Vm (300 kgf Vcm, 22 ft Vlbf)
33. CONNECT VACUUM HOSES
Connect the following hoses:(1) Vacuum hose to brake booster union
(2) Vacuum hose (from VSV for heater water valve) to
air intake chamber
34. INSTALL THROTTLE BODY (a) Connect the following hoses:(1) Water by±pass hose to throttle body
(2) PCV hose to throttle body
(b) Install a new gasket and throttle body with the two bolts and two nuts.
Torque: 18 N Vm (185 kgf Vcm, 13 ft Vlbf)
HINT: Use bolts 40 mm (1.57 in.) in length.
(c) Install the water by±pass pipe (from rear water bypass
joint) to the clamp on the engine wire cover.
(d) Connect the following connectors: (1) Throttle position sensor connector
(2) (w/ TRAC) Sub±throttle position sensor connector
(3) (w/ TRAC) Sub±throttle actuator connector
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ENGINE MECHANICAL Cylinder HeadsEM±109
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