1991 LEXUS SC400 check oil

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.
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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
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40. RECONNECT NEGATIVE TERMINAL CABLE TOBATTERY
41. REFILL WITH ENGINE COOLANT
42. START ENGINE AND CHECK FOR LEAKS
EG21T±02
IGNITION TIMING INSPECTION
1. REMOVE UPPER HIGH±TENSION CORD COVER
(a) Remove the 2 bolts.
(b) Disconnect the front side claw groove of the upper cord cover
from the claw of lower cord cover, and remove the upper cord
cover.
2. WARM UP ENGINE Allow the engine to warm up to normal operating tempera-
ture.
3. CONNECT TACHOMETER AND TIMING LIGHT TO ENGINE
Connect the tester probe of a tachometer to terminal IG
of
the DLC1.
HINT: Set the tachometer to the 4±cylinder range.
NOTICE:
w Never allow the tachometer terminal to touch ground as
it could result in damage to the igniter and/or ignition
coil.
w As some tachometers are not compatible with this
ignition system, we recommend that you confirm the
compatibility of your unit before use.
4. INSPECT IGNITION TIMING
(a) Using SST, connect terminals TE1 and E1 of the DLC 1.
SST 09843±18020
EG±32
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EG115±06
IDLE SPEED INSPECTION
1. INITIAL CONDITIONS
(a) Engine at normal operating temperature
(b) Air cleaner installed
(c) All pipes and hoses of air induction system connected
(d) All accessories switched OFF
(e) All vacuum lines properly connectedHINT: All vacuum hoses for EGR system, etc. should be prop-
erly connected.
(f) MFI system wiring connectors fully plugged
(g) Ignition timing set correctly
(h) Transmission in neutral position
2. CONNECT TACHOMETER Connect the tester probe of a tachometer to terminal IG
of
the DLC1.
HINT: Set the tachometer to the 4±cylinder range.
NOTICE:
w Never allow the tachometer terminal to touch ground as
it could result in damage to the igniter and/or ignition
coil.
w As some tachometers are not compatible with this
ignition system, we recommend that you confirm the
compatibility of your unit before use.
3. INSPECT IDLE SPEED
(a) Race the engine speed at 2,500 rpm for approx. 90 seconds.
(b) Check the idle speed.
Idle speed:
700 + 50 rpm
If the idle speed is not as specified, check the IAC valve.
4. DISCONNECT TACHOMETER
EG±34
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COMPRESSION CHECK
EG21U±02
HINT: If there is lack of power, excessive oil consumption or
poor fuel economy, measure the compression pressure.
1. WARM UP AND STOP ENGINE Allow the engine to warm up to normal operating tempera-
ture.
2. DISCONNECT NEGATIVE TERMINAL CABLE FROM BATTERY
CAUTION: Work must be started after 90 seconds from
the time the ignition switch is turned to the ªLOCKº posi-
tion and the negative (±) terminal cable is disconnected
from the battery.
3. REMOVE INTAKE AIR CONNECTOR
(a) Disconnect the following hoses: (1) Air hose from IAC valve
(2) Air hose (from air control valve on PS pump) from intake
air connector
(b) Remove the bolt holding the intake air connector to the cylinder head cover.
(c) Remove the 2 hose clamps.
(d) Disconnect the intake air connector from the throttle body
and air cleaner hose, and remove the intake air connector.
4. REMOVE UPPER HIGH±TENSION CORD COVER
(a) Remove the 2 bolts.
(b) Disconnect the front side claw groove of the upper cord cover
from the claw of lower cord cover, and remove the upper cord
cover.
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15. CHECK CYLINDER COMPRESSION PRESSURE
(a) Reconnect the battery negative (±) cable.
(b) Insert a compression gauge into the spark plug hole.
(c) Fully open the throttle.
(d) Wh ile cra n kin g th e en g in e , me a su re th e co mp re ssio npressure.
HINT: Always use a fully charged battery to obtain engine
speed of 250 rpm or more.
(e) Repeat steps (b) through (d) for each cylinder. NOTICE: This measurement must be done in as short a
time as possible.
Compression pressure:
1,226 kPa (12.5 kgf/cm
2, 178 psi) or more
Minimum pressure: 981 kPa (10.0 kgf/cm
2, 142 psi)
Difference between each cylinder: 98 kPa (1.0 kgf/cm
2, 14 psi) or less
(f) If the cylinder compression in one or more cylinders is low,pour a sm all amount of engine oil into the cylinder through the
spark plug hole and repeat steps (b) through (d) for cylinders
with low compression.
w If adding oil helps the compression, it is likely that the
piston rings and/or cylinder bore are worn or damage.
w If pressure stays low, a valve may be sticking or seating
is improper, or there may be leakage past the gasket.
(g) Disconnect the battery negative (±) cable.
16. REINSTALL SPARK PLUGS
Using a 16 mm plug wrench, install the 8 spark plugs.
Torque: 18 N Vm (180 kgf Vcm, 13 ft Vlbf)
17. R E C O N N E C T H I G H ± T E N S I O N C O R D S TO S PA R K
PLUGS
18. RECONNECT RH CAMSHAFT POSITION SENSOR CONNECTOR
(a) Connect the camshaft position sensor connector.
(b) Install the camshaft position sensor connector to the ignition
coil bracket.
EG±40
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39. REMOVE CRANKSHAFT TIMING PULLEYUsing SST, remove the timing pulley.
SST 09213±60017 (09213±00050)
EG1KH±02
TIMING BELT COMPONENTS
INSPECTION
1. INSPECT TIMING BELT
NOTICE:
w Do not bend, twist or turn the timing belt inside out.
w Do not allow the timing belt to come into contact with oil,
water or steam.
w Do not utilize timing belt tension when installing or
removing the mounting bolt of the camshaft timing
pulley.
If there are any defects as shown in the illustration, check the
following points:
(a) Premature parting wCheck the proper installation.
w Check the timing cover gasket for damage and proper
installation.
(b) If the belt teeth are cracked or damaged, check to see if either
camshaft or water pump is locked.
(c) If there is noticeable wear or cracks on the belt face, check to see if there are nicks on the side of the idler pulley lock.
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(d) If there is wear or damage on only one side of the belt, checkthe belt guide and the alignment of each pulley.
(e) If there is noticeable wear on the belt teeth, check the timing cover for damage, gasket has been installed correctly, and
the foreign material on the pulley teeth. If necessary, replace
the timing belt.
2. INSPECT IDLER PULLEYS Check that the idler pulley turns smoothly.
If necessary, replace the idler pulley.
3. INSPECT TIMING BELT TENSIONER
(a) Visually check tensioner for leakage. HINT: If there is only the faintest trace of oil on the seal on the
push rod side, the tensioner is all right.
If leakage is found, replace the tensioner.
(b) Hold the tensioner with both hands, and push the push rod firmly against floor or wall to check that it doesn't move.
If push rod moves, replace the tensioner.
EG±58
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