1991 LEXUS SC400 engine oil

REMOVAL OF HYDRAULIC PUMP
(See Components on page CO±26)
1. REMOVE BATTERY CAUTION: Work must be started after approx. 20 se-
conds or longer from the time the ignition switch is
turned to the ºLOCKº position and the negative (±) termi-
nal cable is disconnected from the battery.
2. REMOVE ENGINE UNDER COVER
3. DRAIN ENGINE COOLANT (See page CO±6)
4. REMOVE DRIVE BELT Loosen the drive belt tension by turning the drive belt tension-
er counterclockwise, and remove the drive belt.
HINT: The pulley bolt for the belt tensioner has a left±hand
thread.
5. DISCONNECT A/C COMPRESSOR (a) Disconnect the A/C compressor connector.
(b) Remove the nut, and disconnect the ground cable.
(c) Remove the bolt and A/C compressor stay.
(d) R e m o v e t h e t w o b o l t s , a n d d i s c onnect the A/C
compressor from the engine.
6. REMOVE LH IGNITION COIL (a) Disconnect the following connectors and cord:(1) Ignition coil connector
(2) Noise filter connector
(3) High±tension cord
±
COOLIING SYSTEM Electronically Controlled Hydraulic
Cooling Fan (Hydraulic Pump)CO±27
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(b) Remove the two bolts and ignition coil.
7. REMOVE INTAKE AIR CONNECTOR (a) Disconnect the following hoses:(1) Air hose from ISC valve
(2) Air hose (from PS air control valve) from intake air
connector
(b) Remove the bolt holding the intake air connector to the cylinder head cover.
(c) Loosen the two hose clamps.
(d) Disconnect the intake air connector from the throttle
body and air cleaner hose, and remove the throttle body.
8. REMOVE UPPER HIGH±TENSION CORD COVER (a) Remove the two mounting bolts.
(b) Disconnect the front side claw groove of the cord coverfrom the claw of the lower cover, and remove the cord
cover.
9. REMOVE RH ENGINE WIRE COVER Remove the bolt and engine wire cover.
CO±28
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COOLIING SYSTEM Electronically Controlled Hydraulic
Cooling Fan (Hydraulic Pump)
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15. REMOVE RH NO.2 TIMING BELT COVER(a) Disconnect the cam position sensor connector from theignition coil bracket.
(b) Disconnect the cam position sensor wire from the clamp
on the timing belt cover.
(c) Remove the five mounting bolts.
(d) Disconnect the wire clamp from the timing belt cover,
and remove the timing belt cover and four gasket.
16. REMOVE LH NO.2 TIMING BELT COVER (a) Disconnect the cam position sensor wire from the clamp
on the timing belt cover.
(b) Disconnect the cam position sensor connector.
(c) Remove the three mounting bolts.
(d) Disconnect the connector grommet from the timing belt cover, and remove the timing belt cover and two
gaskets.
17. DISCONNECT PRESSURE AND SUCTION HOSES FROM HYDRAULIC PUMP
18. REMOVE HYDRAULIC PUMP (a) Disconnect the solenoid valve connector.
(b) Remove the two mounting bolts and two nuts.
(c) Disconnect the engine speed sensor wire clamp.
(d) Remove the hydraulic pump.
CO±30
±
COOLIING SYSTEM Electronically Controlled Hydraulic
Cooling Fan (Hydraulic Pump)
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INSTALLATION OF HYDRAULIC PUMP
(See Components on page CO±26)
1. INSTALL HYDRAULIC PUMP (a) Install the hydraulic pump, solenoid valve connector
clamp and engine speed sensor wire clamp with the two
bolts and two nuts.
Torque:
12 mm head 16 N Vm (160 kgf Vcm, 12 ft Vlbf)
14 mm head 20 N Vm (310 kgf Vcm, 22 ft Vlbf)
HINT: Each bolt length is indicated in the illustration.
Bolt length:
A 106 mm (4.17 in.) for 12 mm head
B 114 mm (4.49 in.) for 14 mm head
(b) Connect the solenoid valve connector.
2. CONNECT PRESSURE AND SUCTION HOSES TO HYDRAULIC PUMP
(a) Connect the pressure hose with new gasket and unionbolt.
Torque: 64 N Vm (650 kgf Vcm, 47 ft Vlbf)
(b) Connect suction hose.
3. 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: 16 N Vm (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 wire to the wire clamp on
the timing belt cover.
(f) Install the cam position sensor connector to the ignition coil bracket.
4. 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) In sta ll th e ca m po sitio n se n so r c onnector to the
connector bracket.
(f) Install the cam position sensor wire to the wire clamp on
the timing belt cover.
(g) Install the connector grommet to the timing belt cover.
CO±42
±
COOLIING SYSTEM Electronically Controlled Hydraulic Cooling Fan
(Hydraulic Pump)
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4. REMOVE OIL COOLERRemove the three bolts and oil cooler.
INSPECTION OF OIL COOLER
INSPECT OIL COOLER
Check the oil cooler for damage or clogging.
If necessary, replace the oil cooler.
INSTALLATION OF OIL COOLER
(See Components on page CO±58)
1. INSTALL OIL COOLER Install the oil cooler with the three bolts.
Torque: 18 N Vm (180 kgf Vcm, 13 ft Vlbf)
2. CONNECT HOSES FROM OIL COOLER
Connect the following hoses:(1) Inlet hose (from reservoir tank)
(2) Outlet hose (from hydraulic motor)
3. INSTALL PS OIL COOLER Install the oil cooler with the two bolts.
4. REMOVE FENDER LINER
5. FILL COOLING FAN RESERVOIR TANK WITH FLUID
(See pages CO±23 and 24)
6. START ENGINE AND CHECK FOR LEAKS
±
COOLIING SYSTEM Electronically Controlled Hydraulic
Cooling Fan (Oil Cooler)CO±59
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TORQUE SPECIFICATIONS
Part tightenedNVmkgf Vcmft Vlbf
Engine drain plug X Cylinder block1818013
Coolant filler plug X Water inlet housing44450 33
Water pump X Cylinder block18185 13
Water inlet housing X Water pump18185 13
Water inlet X Water inlet housing18185 13
Radiator fan shroud X Radiator4.950 43 in. Vlbf
Radiator X Body12120 9
Cooling fan reservoir tank X Radiator fan shroud4.950 43 in. Vlbf
Cooling fan inlet pipe X Radiator fan shroud4.950 43 in. Vlbf
Cooling fan pressure hose X Hydraulic motor64650 47
Radiator reservoir tank X Upper radiator support4.950 43 in. Vlbf
Radiator reservoir tank X Radiator reservoir tank support4.950 43 in. Vlbf
Hydraulic pump rear housing X End plug (for spool valve)19200 14
Hydraulic pump front housing X Rear housing21210 15
Hydraulic pump pulley X Drive shaft59600 43
Solenoid valve X Hydraulic pump rear housing39400 28
Hydraulic pump suction port union X Rear housing13135 10
 Hydraulic pump X Cylinder block 12 mm head 16 160 12
  14 mm head 20 310 22
\
 \
Cooling fan pressure hose X Hydraulic pump 64 650 47
\
 \
RH No.2 timing belt cover X Cylinder block 16 160 12
\
 \
Drive belt idler pulley X Hydraulic pump 37 380 27
\
 \
A/C compressor X Hydraulic pump 49 500 36
\
 \
A/C compressor X Cylinder block 49 500 36\
 \
A/C compressor stay X Oil filter bracket 29 300 22\
 \
Hydraulic motor cover X Motor housing 28 290 21\
 
\

\
Hydraulic motor X Radiator fan shroud
 

4.9
 

50
 

43 in.
Vlbf
\
 \
Cooling fan X Hydraulic motor 15 150 11
\
 \
Cooling fan oil cooler X Body 18 180 13
\
 \
Water temperature sensor X Radiator 7.4 75 65 in. Vlbf
±
COOLIING SYSTEM Service SpecificationsCO±65
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The 1 UZ±FE engine has 8±cylinders in a V±arrangement at a bank an\
gle of 905. From the front of the RH
bank cylinders are numbered 2±4±6±8, and from the front of the LH b\
ank cylinders are numbered 1 ±3±5±7.
The crankshaft is supported by 5 bearings specified by the inside of the cr\
ankcase. These bearings are made
of a copper and lead alloy. The crankshaft is integrated with 8 weights which are cast along with it\
for balancing. Oil holes are built
into the center of the crankshaft for supplying oil to the connecting ro\
ds, pistons and other components. The ignition order is 1±8±4±3±6±5±7±2. The cylinder\
head is made of aluminum alloy, with a cross flow
type intake and exhaust layout and with pent±roof type combustion chambers. The spark plugs are loca\
ted in
the center of the combustion chambers.
At the front and rear of the intake manifold, a water passage has been p\
rovided which connects the RH
and LH cylinder heads. Exhaust and intake valves are equipped with irregular pitch springs made\
of special valve spring carbon
steel which are capable of following no matter what the engine speed.
The RH and LH intake camshafts are driven by a single timing belt, and a ge\
ar on the intake camshaft en-
gages with a gear on the exhaust camshaft to drive it. The camshaft jour\
nal is supported at 5 (intake) or 4 (ex-
haust) places between the valve lifters of each cylinder and on the front end of the cylinder \
head. Lubrication
of the cam journal gear is accomplished by oil being supplied through the \
oiler port in the center of the camshaft. Adjustment of the valve clearance is done by means of an outer shim type\
system, in which valve adjusting
shims are located above the valve lifters. This permits replacement of the sh\
ims without removal of the cam-
shafts. Pistons are made of high temperature±resistant aluminum alloy, and a depression is built into the piston
head to prevent interference with valves.
Piston pins are the full±floating type, with the pins fastened to neither the piston boss nor the connecting
rods. Instead, snap rings are fitted on both ends of the pins, preventing the\
pins from falling out. The No.1 compression ring is made of steel and the No.2 compression ring\
is made of cast iron. The oil
ring is m ade of a combination of steel and stainless steel. The outer diameter of\
each piston ring is slightly larger
than the diameter of the piston and the flexibility of the rings allows them\
to hug the cylinder walls when they
are mounted on the piston. Compression rings No.1 and No.2 work to prevent \
the leakage of gas from the cylin-
der and the oil ring works to scrape oil off the cylinder walls to prevent it from entering the combustion chamber. The cylinder block is made of aluminum alloy with a bank angle of 90 5. Cast iron cylinders are installed
inside the cylinder block. It has 8 cylinders which are approximately twice the length of th\
e piston stroke. The
top of each cylinder is closed off by the cylinder heads and the lower end of the cylinders becomes the crank-
case, in which the crankshaft is installed. In addition, the cylinder bl\
ock contains a water jacket, through which
coolant is pumped to cool the cylinders. The No.1 and No.2 oil pans are bolted onto the bottom of the cylinder block\
. The No.1 oil pan is made of
aluminum alloy. The No.2 oil pan is an oil reservoir made of pressed steel sheet. An o\
il level sensor is installed
in the No.1 oil pan (If the oil level drops below a set level, a warnin\
g light lights up.). A oil pan baffle plate keeps
sufficient oil in the bottom of the No.2 oil pan even when the vehicle is tilted. \
This dividing plate also prevents
the oil from making waves when the vehicle is stopped suddenly and the oil \
shifts away from the oil pump suction
pipe. Plastic region tightening bolts are used for the cylinder head, main bearing ca\
p and connecting rod.
EM±4
±
ENGINE MECHANICAL Operation
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EQUIPMENT
 


Part Name\
 
\

\
Note
 Caliper gauge\
 \

 


HC/CO meter
\
 
\

\

 


Compression gauge\
 
\

\
Cylinder compression pressure
 Connecting rod aligner\
 \

 


Cylinder gauge
\
 
\

\

 


Dial indicator
\
 
\

\

 


Engine turn±up tester\
 
\

\

 Feeler gauge\
 \

 


Micrometer
\
 
\

\

 


Precision straight edge\
 
\

\

 Spring tester\
 \
Valve spring
 


Steel square
\
 
\

\
Valve spring
 


Torque wrench\
 
\

\

 Vernier caliper\
 \

SSM (SPECIAL SERVICE MATERIALS)
 
Part Name
 
Part No.
\
 \

Use etc.  \
 \

Camshaft bearing cap  \
 \
Camshaft bearing ca
Cylinder head semi±circular plug 
Seal packing or equivalent
 
08826±00080
\
 \
Cylinder head semi±circular lug
Cylinder head cover Seal acking or equivalent 08826±00080\
 \
Cylinder head cover
Rear oil seal retainer  \
 \
Rear oil seal retainer
Oil pump  \
 \

Water inlet housing Seal packing 1282B,
Th b d 1282B i l t
 08826±00100\
 \
Water inlet housing
Water seal plate Three bond 1282B or equivalent 08826±00100\
 \
Water seal late
Water pump 

Adhesive 1324,
Three bond 1324 or equivalent
 

08833±00070
\
 

\
Drive plate mounting bolt
 
Adhesive 1344,
 \
 \

 Adhesive 1344,
Three bond 1344
,
 
08833±00080
\
 \

No.1 idler pulley mounting bolt Three bond 1344,
Loctite 242 or equivalent 08833±00080\
 \
No.1 idler ulley mounting bolt
±
ENGINE MECHANICAL PreparationEM±7
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