engine LEXUS SC400 1991 Service Repair Manual
Page 2171 of 4087
19. BRAKE PEDAL
(a) Check that pedal for smooth operation.
(b) Check that the pedal has the proper reservedistance and freeplay.
(c) Check the brake booster function.
20. BRAKES At a safe place, check that the brakes do not
pull to one side when applied.
21. PARKING BRAKE
(a) Check that the pedal has the proper travel.
(b) On a safe incline, check that the vehicle is held securely with only the parking brake applied.
22. A U TO M AT I C T RANSMISSION PARK
MECHANISM
(a) Check the lock release button of the selector lever for proper and smooth operation.
(b) On a safe incline, check that the vehicle is held securely with the selector lever in the ªPº
position and all brakes released.
MA00T±0A
UNDER HOOD
23. WINDSHIELD WASHER FLUIDCheck that there is sufficient fluid in the tank.
24. ENGINE COOLANT LEVEL
Check that the coolant level is between the
LEVEL lines on the see±through reservoir at
normal temperature (20 5C (68 5F)).
25. RADIATOR AND HOSES
(a) Check that the front of the radiator is clean and not blocked with leaves, dirt or bugs.
(b) Check the hoses for cracks, kinks, rot or loose connections.
26. BATTERY ELECTROLYTE LEVEL
Check the indicator.
When the indicator color is blue, the condition
is satisfactory. A red color indicates that dis-
tilled water must be added, and white indicates
that charging is necessary. 27. BRAKE FLUID LEVEL
Check that the brake fluid level is near the up-
per level line on the see±through reservoir.
28. ENGINE DRIVE BELT Check drive belt for fraying, cracks, wear or oili-
ness.
29. ENGINE OIL LEVEL
Check that level on the dipstick with the engine
turned off.
30. POWER STEERING FLUID LEVEL Check the level on the dipstick.
The level should be in the ªHOTº or ªCOLDº
range depending on the fluid temperature.
31. AUTOMATIC TRANSMISSION FLUID LEVEL
(a) Park the vehicle on a level surface.
(b) With the engine idling and the parking and foot brake applied, shift the selector into all
positions from ªPº to ªLº, and then shift into ªPº.
(c) Turn and pull out the dipstick and wipe off the fluid with a clean rag.
Re±insert the dipstick fully and check that the
fluid level is in the ªHOTº range.
(d) Perform this check with the fluid at normal driving temperature (70 ± 80 C (158 ± 176 F)).
If the level is at the low side, add fluid.
NOTICE: Do not overfill.
HINT: Wait about 30 minutes before checking
the fluid level after extended driving at high
speeds in hot weather, driving in heavy traffic
or with a trailer.
32. EXHAUST SYSTEM Visually inspect for cracks, holes or loose sup-
ports.
If any change in the sound of the exhaust or
smell of the exhaust fumes is noticed, have the
cause located and corrected.
MA±20
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MAINTENANCE (1UZ ± FE)
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Page 2174 of 4087
DESCRIPTION
(SC400)
PR02N±04
The propeller shaft is a 2±part type, each part consisting of a strong, \
compact precisely balanced tube. The
propeller shaft is connected to the transmission and the differential via 3 joints. No.1 and No.3 joints are
made of flexible rubber couplings. No.2 joint is a Hooke's universal joint. All 3 joints are carefully arranged
in such a way that their shaft angles rest on a straight line. This design\
ensures a precise drive line linearity
from the engine through the differential to minimize noise and vibration.
A shaft length adjusting mechanism is incorporated in order to make prope\
ller shaft removal and reinstalla-
tion easier.
PR±2±
PROPELLER SHAFT DESCRIPTION (SC400)
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Page 2208 of 4087
ENGINE TUNE±UP
INSPECTION OF ENGINE COOLANT
1. INSPECT ENGINE COOLANT LEVEL AT RESERVOIRTANK
The coolant level should be above the ºCOLD LEVELº at
normal temperature (20 5C (68 5F)).
If low, check for leaks and add coolant up to the ºCOLD
LEVELº.
2. INSPECT ENGINE COOLANT QUALITY There should be any excessive deposits of rust or scales
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.
INSPECTION OF ENGINE OIL
1. INSPECT ENGINE OIL QUALITYCheck the oil for deterioration, entry of water, discoloring or
thinning.
If the quality is poor, replace the oil.
Oil grade: API grade SG, Energy±Conserving II multigrade.
Recommended viscosity is as shown, with SAE
5W±30 being the preferred engine oil.
Drain and refill oil capacity: w/ oil filter change4.8 liter (5.1 US qts, 4.2 lmp. qts)
w/o oil filter change 4.5 liter (4.8 US qts, 4.0 lmp. qts)
2. INSPECT ENGINE OIL LEVEL The oil level should be between the ºLº and ºFº marks on the
dipstick.
If low, check for leakage and add oil up to ºFº mark.
EM±8
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ENGINE MECHANICAL Engine Tune±Up
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Page 2209 of 4087
INSPECTION OF BATTERY
1. INSPECT BATTERY SPECIFIC GRAVITY ANDELECTROLYTE LEVEL
(a) Check the specific gravity of each cell.
Standard specific gravity:
1.27±1.29 when fully charged at 20 5C(68 5F)
If not within specification, charge the battery.
(b) Check the electrolyte quantity of each cell.
If insufficient, refill with distilled (or purified) water.
2. CHECK BATTERY TERMINALS Check that the battery terminals are not loose or corroded.
INSPECTION AND CLEANING OF AIR
FILTER
1. REMOVE AIR FILTER(a) Open the air cleaner cap.
(b) Remove the air filter.
2. INSPECT AIR FILTER (a) Visually check that the air filter is not excessivelydamaged or oily.
(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
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ENGINE MECHANICAL Engine Tune±UpEM±9
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Page 2210 of 4087
INSPECTION OF HIGH±TENSION CORDS
1. REMOVE HIGH±TENSION CORDS (See page IG±11)
2. INSPECT HIGH±TENSION CORDS (b) Using an ohmmeter, measure the resistance.
Maximum resistance: 25 k per cord
If the resistance is greater than maximum, replace the cord.
3. REINSTALL HIGH±TENSION CORDS (See page IG±16)
INSPECTION OF DRIVE BELT
INSPECT DRIVE BELT
HINT: A belt tensioner is used, so checking the belt tension
is not necessary.
(a) Visually check the drive belt for excessive wear, frayedcords etc.
If necessary, replace the drive belt.
HINT:
w Cracks on rib side of a drive belt are considered
acceptable. If the drive belt has chunks missing from the
ribs, it should be replaced.
w The drive belt tension can be released by turning the
belt tensioner counterclockwise. The pulley bolt for the
belt tensioner has a left±hand thread.
(b) Check the belt tensioner operation. w Check that the belt tensioner moves downward
when the drive belt is pressed down at the points
indicated in the illustration with approx. 98 N (10
kgf, 22.0 lbf) of force.
w Check the alignment of the belt tensioner pulley to
make sure the drive belt has not slipped off the
pulley.
If necessary, replace the belt tensioner. w Check that the arrow mark on the belt tensioner
falls within area A of the scale.
If it is outside area A, replace the drive belt.
HINT:
w When a new belt is installed, it should lie within area B.
If not, the drive belt is not correct.
w After installing a belt, check that it fits properly in the
ribbed grooves.
w Check by hand to confirm that the belt has not slipped
out of the groove on the bottom of the pulley.
EM±10
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ENGINE MECHANICAL Engine Tune±Up
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INSPECTION AND ADJUSTMENT OF
VALVE CLEARANCE
HINT: Inspect and adjust the valve clearance when the
engine is cold.
1. DISCONNECT CABLE FROM NEGATIVE TERMINAL OF 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. DRAIN ENGINE COOLANT (See page CO±6)
3. REMOVE THROTTLE BODY COVER (a) Remove the mounting cap nut.
(b) Loosen the two bolts, and remove the throttle body
cover.
4. DISCONNECT CONTROL CABLES FROM THROTTLE BODY
Disconnect the following cables:(1) Accelerator cable
(2) A/T throttle control cable
(3) (w/ Cruise Control System) Cruise control actuator cable
5. 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.
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ENGINE MECHANICAL Engine Tune±UpEM±11
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Page 2212 of 4087
6. 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.
7. REMOVE RH ENGINE WIRE COVER Remove the bolt and engine wire cover.
8. REMOVE LH ENGINE WIRE COVER Remove the two bolts and engine wire cover.
9. REMOVE VSV FOR EVAP SYSTEM Remove the two bolts, and disconnect the VSV from cylinder
head and timing belt cover.
10. REMOVE RH NO.3 TIMING BELT COVER Remove the three bolts and timing belt cover.
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ENGINE MECHANICAL Engine Tune±Up
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Page 2213 of 4087
11. DISCONNECT FUEL INLET HOSE FROM LH DELIVERYPIPE
Remove the pulsation damper and two gaskets, and discon-
nect the inlet hose.
12. D I S C O N N E C T F U E L R E T U R N H O S E F R O M F U E L RETURN PIPE
13. DISCONNECT PCV HOSE FROM LH CYLINDER HEAD
14. REMOVE LH NO.3 TIMING BELT COVER (a) Remove the four mounting bolts.
(b) Disconnect the cord grommet from the timing belt cover,
and remove the timing belt cover.
(c) Remove the cord grommet from the high±tension cord.
15. DISCONNECT HEATER WATER VALVE FROM BODY (a) Disconnect the VSV connector.
(b) Remove the bolt holding the engine wire clamp to thewater valve bracket.
(c) Remove the two bolts, and disconnect the water valve and bracket assembly.
16. REMOVE THROTTLE BODY (a) Disconnect the following connectors:(1) Throttle position sensor connector
(2) (w/ TRAC)
Sub±throttle position sensor connector
(3) (w/ TRAC) Sub±throttle actuator connector
(b) Disconnect the following hoses: (1) Water by±pass hose from ISC valve
(2) (USA Spec.) Vacuum hose from throttle body
(3) (Exc. USA Spec.) Three vacuum hoses from throttle body
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Page 2214 of 4087
(c) Remove the two bolts and two nuts, disconnect thethrottle body from the air intake chamber.
(d) Disconnect the following hoses, and remove the throttle body:
(1) PCV hose from throttle body
(2) Water by±pass hose from throttle body
(e) Remove the throttle body gasket.
17. REMOVE RH CYLINDER HEAD COVER (a) Remove the two bolts holding the cord clamp to thecylinder head.
(b) Disc onnect the high±tension cords from the spark
plugs.
(c) Disconnect the high±tension cords from the front high±tension cord clamp.
(d) Remove the eight bolts, seal washers, cylinder head cover and gasket.
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ENGINE MECHANICAL Engine Tune±Up
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Page 2215 of 4087
16. REMOVE LH CYLINDER HEAD COVER(a) Remove the two bolts holding the high±tension cordclamp to the cylinder head.
(b) Disc onnect the high±tension cords from the spark
plugs.
(c) Disconnect the high±tension cords from the front high±tension cord clamp.
(d) Disconnect the engine wire from the two wire clamps on
the LH delivery pipe.
(e) Disconnect the four injector connectors.
(f) Disconnect the two engine wire connectors.
(g) Remove the eight bolts, seal washers, cylinder head
cover and gasket.
19. SET NO.1 CYLINDER TO TDC/COMPRESSION (a) Turn the crankshaft pulley, and align its groove with thetiming mark º0º of the No.1 timing belt cover.
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ENGINE MECHANICAL Engine Tune±UpEM±15
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