ect LEXUS SC300 1991 Service Repair Manual

B. Install cylinder head boltsHINT:
wThe cylinder head bolts are tighten in two progressive
steps (steps (c) and (e)).
w If any one of the cylinder head bolts broken or deformed,
replace it.
(a) Apply a light coat of engine oil on the threads and under
the heads of the cylinder head bolts.
(b) Te mp o ra rily in sta ll th e twe n ty pla te wa sh e rs an d cylinder head bolts.
(c) Uniformly tighten the ten cylinder head bolts on one side
of the cylinder head in several passes in the sequence
shown, then do the other side as shown.
Torque: 39 N Vm (400 kgf Vcm, 29 ft Vlbf)
If any one of the bolts does not meet the torque specification,
replace the bolt.
(d) Mark the front of the cylinder head bolt head with paint.
(e) Retighten the cylinder head bolts 90 ° in the numerical
order shown.
(f) Check that the painted mark is now at a 90 ° angle to
front.
4. CONNECT MAIN OXYGEN SENSOR CONNECTORS Connect the RH and LH oxygen sensor connector.
5. INSTALL CIRCULAR PLUGS (a) Place two new circular plugs in position on the cylinderheads, facing the cup side forward.
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(f) Install the other bearing caps in the sequence shownwith the arrow mark facing rearward.
HINT: Align the arrow marks at front and rear of the cylinder
head with the mark on the bearing cap.
(g) Apply a light coat of engine oil on the threads and under
the heads (A only) of the bearing cap bolts.
HINT: Do not apply engine oil under the heads of the bearing
cap bolts (B).
(h) Install a new seal washer to the bearing cap bolt (B).
Install the eight bearing cap bolts as shown.
HINT:
w Use bearing cap bolts 38 mm (1.50 in.) in length. The
bolts are black (A) or silver (B) in color. Install the two
silver bolts to the front bearing cap. Install the six black
bolts to the other positions.
w After installing the oil feed pipe, install the two bolts to
the rear bearing cap as directed in step B (i).
(i) Uniformly tighten the eight bearing cap bolts in several passes in the sequence shown.
Torque: 16 N Vm (160 kgf Vcm, 12 ft Vlbf)
B. Install exhaust camshaft to RH cylinder head
(a) Set the timing mark ( one dot mark) of the camshaft drive
gear at 105 angle by turning the hexagon wrench head
portion of the intake camshaft with a wrench.
(b) Apply MP grease to the thrust portion of the exhaust camshaft.
(c) Align the timing marks (one dot mark) of the camshaft
drive and driven gears.
(d) Place the exhaust camshaft on the cylinder head.
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(e) Check that the exhaust camshaft moves smoothly in the
thrust direction.
(f) Install the rear bearing cap with the arrow mark facing rearward.
HINT:
w Installing the rear 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 rearward.
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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(f) Install the other bearing caps in the sequence shownwith 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.
(g) Apply a light coat of engine oil on the threads and under
the heads (A only) of the bearing cap bolts.
HINT: Do not apply engine oil under the heads of the bearing
cap bolts (B).
(h) Install a new seal washer to the bearing cap bolt (B).
Install the eight bearing cap bolts as shown.
HINT:
w Use bearing cap bolts 38 mm (1.50 in.) in length. The
bolts are black (A) or silver (B) in color. Install the two
silver bolts to the front bearing cap. Install the six black
bolts to the other positions.
w After installing the oil feed pipe, install the two bolts to
the bearing cap second from the front as directed in step
D (i).
(i) Uniformly tighten the eight bearing cap bolts in several passes in the sequence shown.
Torque: 16 N Vm (160 kgf Vcm, 12 ft Vlbf)
D. Install exhaust camshaft to LH cylinder head
(a) Set the timing mark (two dot marks) of the camshaftdrive gear at 15 ° angle by turning the hexagon wrench
head portion of the intake camshaft with a wrench.
(b) Apply MP grease to the thrust portion of the exhaust camshaft.
(c) Align the timing marks (two dot marks) of the camshaft
drive and driven gears.
(d) Place the exhaust camshaft on the cylinder head.
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(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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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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