ect LEXUS SC300 1991 Service Repair Manual

COMPONENTS
REPLACEMENT OF CATALYTIC
CONVERTERS
(Front Catalytic Converter)
1. REMOVE CATALYTIC CONVERTER (FRONT)(a) Check that the converter is cool.
(b) Remove the two bolts and nuts holding the catalyticconverters to the front exhaust pipe.
(c) Disconnect the front exhaust pipe from the catalytic converter, and remove the gasket.
(d) Remove the four nuts holding the catalytic converter to the exhaust manifold.
2. REINSTALL CATALYTIC CONVERTER (a) Install a new gasket and the catalytic converter to theexhaust manifold with four new nuts.
Torque: 62 N Vm (630 kgf Vcm, 46 ft Vlbf)
(b) Install a new gasket to front end of the front exhaust
pipe, and torque the front exhaust pipe to the catalytic
converter.
Torque: 43 N Vm (440 kgf Vcm, 32 ft Vlbf)
EC±18±
EMISSION CONTROL SYSTEMS Three±way Catalyst (TWC) System
WhereEverybodyKnowsYourName

SERVICE SPECIFICATIONS
SERVICE DATA
EG065±0A Tune±up Battery specific gravity  1.27±1.29
    (when fully charged at 205C (68 5F))
  High±tension cord resistance Limit 25 k
per cord
  Valve clearance (Cold) Intake 0.15±0.25 mm (0.006±0.010 in.)
   Exhaust 0.25±0.35 mm (0.010±0.014 in.)
Valve clearance adjusting shimNo.012.500 mm (0.0984 in.)   No.62 2.525 mm (0.0994 in.)   No.63 2.550 mm (0.1004 in.)   No.64 2.575 mm (0.1014 in.)   No.06 2.600 mm (0.1024 in.)
   No.65 2.625 mm (0.1033 in.)
   No.66 2.650 mm (0.1043 in.)
   No.67 2.675 mm (0.1053 in.)
   No.13 2.700 mm (0.1063 in.)
   No.68 2.725 mm (0.1073 in.)
   No.18 2.750 mm (0.1083 in.)
No.192.775 mm (0.1093 in.)   No.23 2.800 mm (0.1102 in.)   No.70 2.825 mm (0.1112 in.)   No.28 2.850 mm (0.1122 in.)   No.71 2.875 mm (0.1132 in.)
   No.33 2.900 mm (0.1142 in.)
   No.72 2.925 mm (0.1152 in.)
   No.38 2.950 mm (0.1161 in.)
   No.73 2.975 mm (0.1171 in.)
   No.43 3.000 mm (0.1181 in.)
No.743.025 mm (0.1191 in.)   No.48 3.050 mm (0.1201 in.)   No.75 3.075 mm (0.1211 in.)   No.51 3.100 mm (0.1220 in.)   No.76 3.125 mm (0.1230 in.)   No.77 3.150 mm (0.1240 in.)
   No.78 3.175 mm (0.1250 in.)
   No.56 3.200 mm (0.1260 in.)
   No.79 3.225 mm (0.1270 in.)
   No.80 3.250 mm (0.1280 in.)
   No.81 3.275 mm (0.1289 in.)
No.613.300 mm (0.1299 in.)  Ignition timing  8 ± 12 5 BTDC @ idle 


 


 


 

(w/ Terminals TE1 and E1 connected
of DLC1)
  Idle speed  700
+ 50 rpm
 Intake at idle speed  60 kPa (450 mmHg. 17.7 in.Hg)
 manifold
 vacuum   
±
1UZ ± FE ENGINE ENGINE MECHANICALEG±205
WhereEverybodyKnowsYourName

 
Piston and Piston diameter STD (Mark1) 87.470±87.480 mm (3.4437±3.4441 in.)
 piston ring  (Mark 2) 87.480±87.490 mm (3.4441±3.4445 in.)   (Mark 3) 87.490±87.500 mm (3.4445±3.4449 in.)  Piston oil clearance STD 0.020±0.040 mm (0.0008±0.0016)   Limit 0.06 mm (0.0024 in.)  Piston ring groove clearance No.1 0.020±0.060 mm (0.0008±0.0024 in.)   No.2 0.015±0.055 mm (0.0006±0.0022 in.)  Piston ring end gap STD (No.1) 0.250±0.450 mm (0.0098±0.0177 in.)
   (No.2) 0.350±0.600 mm (0.0138±0.0236 in.)
   (Oil) 0.150±0.500 mm (0.0059±0.0197 in.)
   Limit (No.1) 1.05 mm (0.0413 in.)
   (No.2) 1.20 mm (0.0472 in.)
   (Oil) 1.10 mm (0.0433 in.)
 Connecting Thrust clearance STD 0.160±0.290 mm (0.0063±0.0138 in.)
 rod  Limit 0.35 mm (0.0138 in.)
  Connecting rod thickness  22.880±22.920 mm (0.9008±0.9024 in.)
  Connecting rod big end inside diameter (Ref-
erence)  
   Mark 1 55.000±55.006 mm (2.1654±2.1656 in.)   Mark 2 55.006±55.012 mm (2.1656±2.1658 in.)   Mark 3 55.012±55.018 mm (2.1658±2.1661 in.)   Mark 4 55.018±55.024 mm (2.1661±2.1663 in.)  Connecting rod bearing center wall thickness  
  (Reference) Mark 2 1.484±1.487 mm (0.0584±0.0585 in.)   Mark 3 1.487±1.490 mm (0.0585±0.0587 in.)
   Mark 4 1.490±1.493 mm (0.0587±0.0588 in.)
   Mark 5 1.493±1.496 mm (0.0588±0.0589 in.)
   Mark 6 1.496±1.499 mm (0.0589±0.0590 in.)
   Mark 7 1.499±1.502 mm (0.0590±0.0591 in.)
  Connecting rod oil clearance STD 0.027±0.053 mm (0.0011±0.0021 in.)
   Limit 0.065 mm (0.0026 in.)
 \
 \
Rod bend Limit per 100 mm (3.94 in.) 0.05 mm (0.0020 in.)
 \
 \
Rod twist Limit per 100 mm (3.94 in.) 0.15 mm (0.0059 in.)
  Bushing inside diameter  22.005±22.017 mm (0.8663±0.8668 in.)
  Piston pin diameter  21.997±22.009 mm (0.8660±0.8665 in.)
  Bushing oil clearance STD 0.005±0.011 mm (0.0002±0.0004 in.)
Limit0.05 mm (0.0020 in.)  
Connecting rod bolt tension portion diameter
 
STD
 
7.200±7.300 mm (0.2835±0.2874 in.)   
Limit
 
7.00 mm (0.2756 in.)
EG±208±
1UZ ± FE ENGINE ENGINE MECHANICAL
WhereEverybodyKnowsYourName

 
Front water bypass joint x Cylinder head  18 185 13
 Intake manifold x Cylinder head1818513
Delivery pipe x Intake manifold1818513 
Fuel return pipe x Fuel pressure regulator
  
35
 
360
 
26 Fuel inlet hose x Delivery pipe  39 400 29  for SST 33 340 24 Cold start injector x Air intake chamber  7.8 80 69 in.Vlbf Air intake chamber x Intake manifold  18 185 13 EGR pipe x Air intake chamber  18 185 13
 EGR pipe x RH cylinder head  18 185 13
 Cold start injector tube x Air intake chamber  15 150 11
 Union (for brake booster) x Air intake chamber  29 300 22
 Throttle body x Air intake chamber  18 185 13
 IAC valve x Air intake chamber  18 185 13
 EGR valve adaptor x Air intake chamber  18 185 13
 EGR valve x EGR valve adaptor  18 185 13
Timing belt rear plate x Cylinder head7.88069 in. Vlbf 
Water outlet housing x Water pump
  
18
 
185
 
13 Main bearing stud bolt x Cylinder block  15 150 11 Main bearing cap x Cylinder block for nut (1st) 27 275 20  (2nd) Turn 90 5  
  for bolt 49 500 36 Connecting rod cap x Connecting rod 1st 25 250 18
  2nd Turn 905  
 Rear oil seal retainer x Cylinder block  7.8 80 69 in.Vlbf
 Water seal plate x Cylinder block  14 145 10
 Generator bracket x Cylinder block  18 185 13
 Oil pump x Cylinder block 12 mm head 16 160 12
  14 mm head 30 310 22
 No.1 oil pan x Cylinder block 10 mm head 7.8 80 69 in. Vlbf
12 mm head1818513 
No.1 oil pan x Oil pump
  
7.8
 
80
 
69 in. Vlbf No.1 oil pan x Rear oil seal retainer  7.8 80 69 in. Vlbf Oil strainer x Cylinder block  7.8 80 69 in. Vlbf Oil strainer x Oil pump  7.8 80 69 in. Vlbf Oil pan baffle plate x No.1 oil pan  7.8 80 69 in. Vlbf No.1 oil pan x No.2 oil pan  7.8 80 69 in. Vlbf
 Water pump x Cylinder block  18 185 13
 Water bypass pipe x Cylinder Block  18 185 13
 Knock sensor x Cylinder block  44 450 33
 Starter x Cylinder block  39 400 29
 Engine mounting bracket x Cylinder block  37 380 27
 Drive plate x Crankshaft  98 1,000 72
 Transmission x Cylinder block  57 580 42
 Transmission x No.1 oil pan  39 400 29
Drive plate x Torque converter3334025 Transmission oil cooler pipe x Transmission for union nut 34 350 25 Rear engine mounting member x Body  25 250 19\
 \
Rear engine mounting member x Rear engine mounting insulator1313510
EG±210±
1UZ ± FE ENGINE ENGINE MECHANICAL
WhereEverybodyKnowsYourName

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 t\
he LH bank cylinders are 1 ± 3 ± 5 ± 7.
The crankshaft is supported by 5 bearings inside the crankcase. These beari\
ngs are made of a copper and
lead alloy.
The crankshaft is integrated with 8 weights for balance. Oil holes are plac\
ed in the center of the crankshaft
to supply oil to the connecting rods, bearing, pistons and other component\
s.
The ignition order is 1 ± 8 ± 4 ± 3 ± 6 ± 5 ± 7 ± 2. T\
he cylinder head is made of alminum alloy, with a cross
flow type intake and exhaust layout and with pent±roof type combustion chambers. The spark plugs are
located 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 functioning at all engine speeds.
The RH and LH intake camshaft are driven by a timing belt, and a gear on\
the intake camshaft engages
with a gear on the exhaust camshaft to drive it. The cam journal is supp\
orted at 5 (intake) or 4 (exhaust)
places between the valve lifters of each cylinder and on the front end o\
f the cylinder head. Lubrication of
the cam journals and gears is accomplished by oil being supplied through th\
e 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
camshafts.
Pistons are made of high temperature±resistant aluminum alloy, and a depression is built into the piston
head to prevent interference with the 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 made of a combination of steel and stainless steel. The outer diamet\
er 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 gas leakage from
the cylinder and the oil ring works to scrape oil off the cylinder walls to prevent it from entering the combus-
tion chambers.
The cylinder block is made of aluminum alloy with a bank of 90 5. Cast iron cylinders are installed inside
the cylinder block. It has 8 cylinders which are approximately twice the le\
ngth of the piston stroke. The top
of each cylinder is closed off by the cylinder head and the lower end of the cylinders becomes the crank-
case, in which the crankshaft is installed. In addition, the cylinder block c\
ontains 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 bl\
ock. 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 oil level drops below a set level, a warning light\
s up.). And oil pan baffle plate
keeps sufficient oil in the bottom of the No.2 oil pan even when the vehicle is t\
ilted. This dividing plate also
prevents the oil from marking waves when the vehicle is stopped suddenly\
and the oil shifts away from the
oil pump suction pipe.
Plastic region tighten bolts are used for the cylinder head, main bearin\
g cap and connecting rod.
EG±4
±
1UZ±FE ENGINE ENGINE MECHANICAL
WhereEverybodyKnowsYourName

EG0AZ±06
RECOMMENDED TOOLS
EG0B0±06
EQUIPMENT
\
 \
Battery specific gravity gauge 
\
 
\

\
Caliper gauge 


\
 \
CO/HC meter 
\
 
\

\
Compression gauge
 


\
 
\

\

Connecting rod aligner 


\
 \
Cylinder gauge 
\
 
\

\
Dial indicator 


\
 
\

\

Dye penetrant 


\
 \
Engine tune±up tester 
\
 
\

\
Heater 


\
 \
Magnetic finger 
\
 
\

\
Micrometer
 


\
 
\

\
Piston ring compressor 


\
 \
Piston ring expander 
\
 
\

\
Plastigage
 


\
 
\

\

Precision straight edge 


\
 \
Soft brush 
±
1UZ±FE ENGINE ENGINE MECHANICALEG±7
WhereEverybodyKnowsYourName

TUNE±UP
EG10Z±05
ENGINE COOLANT INSPECTION
1. CHECK ENGINE COOLANT LEVEL AT RESERVOIR TANK
The coolant level should be above the ªCOLD LEVELº at nor-
mal temperature (20 5C (68 5F)).
If low, check for leaks and add coolant up to the ªCOLD LEV-
ELº
2. CHECK ENGINE COOLANT QUALITY
(a) Remove the radiator cap from the reservoir tank.
CAUTION: To avoid the danger of being burned, do not remove
it while the engine and radiator are still hot as fluid and steam
can be blown out under pressure
(b) There should not be any excessive deposits of rust or scale around the radiator cap or reservoir tank filler hole, and the
coolant should be free from oil.
If excessively dirty, clean the coolant passages and replace
the coolant.
Capacity (w/ Heater):
10.8 liters (11.4 US qts, 9.5 lmp. qts)
HINT:
wUse a good brand of ethylene±glycol base coolant and
mix it according to the manufacturer's directions.
w Using coolant which includes more than 50%
ethylene±glycol(but not more than 70%) is
recommended.
NOTICE:
w Do not use a alcohol type coolant.
w The coolant should be mixed with demineralized water or
distilled water.
(c) Reinstall the radiator cap.
±
1UZ±FE ENGINE ENGINE MECHANICALEG±9
WhereEverybodyKnowsYourName

EG0B4±0K
ENGINE OIL INSPECTION
1. CHECK OIL QUALITYCheck the oil for deterioration, entry of water, discoloring or
thinning.
If oil quality is visibly poor, replace the oil.
Oil grade:
API grade SG or SH, Energy±Conserving II or ILSAC
multigrade engine oil. Recommended viscosity is as
shown in the illustration, with SAE 5W±30 being the
preferred engine oil.
Drain and refill capacity: w/ Oil filter change
4.8 liters (5.1 US qts, 4.2 lmp. qts)
w/o Oil filter change
4.5 liters (4.8 US qts, 4.0 lmp. qts)
2. CHECK ENGINE OIL LEVELThe oil level should be between the ªLº and ªFº marks on the
dipstick.
If low, check for leakage and add oil up to the ªFº mark.
EG3E2±01
BATTERY INSPECTION
1. CHECK BATTERY ELECTROYTE LEVEL AND VOLTAGE
(a) Check the electrolyte quantity of each cell.If under the lower level, replace the battery (or add distilled
water if possible.). Need to check the charging system.
(b) Measure the battery voltage between the terminals negative (±) and positive (+) of the battery.
Standard voltage:
12.7±12.9 V at 20 5C (68 5F)
HINT:
w Before measuring the voltage, turn the ignition switch
OFF and turn off the electrical systems (headlight,
blower motor, rear defogger etc.) for 60 seconds to
remove the surface charge.
EG±10
±
1UZ±FE ENGINE ENGINE MECHANICAL
WhereEverybodyKnowsYourName

wIf the vehicle has been running, wait 5 minutes or more
after the vehicle stops before measuring the battery
voltage.
If the voltage is less than specification, charge the battery.
HINT: Check the indicator as shown in the illustration.
1. C H E C K B AT T E RY S P E C I F I C G R AV I T Y A N D ELECTROLYTE LEVEL
2. CHECK BATTERY TERMINALS AND FUSES
(a) Check that the battery terminals are not loose or corroded.
(b) Check the fuses for continuity.
EG3F9±01
AIR FILTER INSPECTION AND
CLEANING
1. REMOVE AIR FILTER
(a) Open the air cleaner cap.
(b) Remove the air filter.
±
1UZ±FE ENGINE ENGINE MECHANICALEG±11
WhereEverybodyKnowsYourName

2. INSPECT AND CLEAN AIR FILTER
(a) Visually check that the air filter is not excessively damagedor only.
If necessary, replace the air filter.
(b) Clean the air filter with compressed air. First blow from the inside thoroughly, then blow off the out-
side of the air filter.
3. REINSTALL AIR FILTER
EG1KB±02
HIGH±TENSION CORDS INSPECTION
1. REMOVE NO.3 TIMING BELT COVERS (See steps 10 to 14 on pages EG±16)
2. REMOVE HIGH±TENSION CORDS (See step 1 on page IG±16)
NOTICE: Pulling on or bending the cords may damage the con-
ductor inside.
3. INSPECT HIGH±TENSION CORD RESISTANCE Using an ohmmeter, measure the resistance.
Maximum resistance:
25 k
per cord
If the resistance is greater than maximum, replace the cord.
4. REINSTALL HIGT±TENSION CORDS (See step 1 on page IG±19)
5. REINSTALL NO.3 TIMING BELT COVERS (See steps 28 to 30 on pages EG±29)
EG±12
±
1UZ±FE ENGINE ENGINE MECHANICAL
WhereEverybodyKnowsYourName