oil pressure LEXUS SC400 1991 Service Manual PDF
[x] Cancel search | Manufacturer: LEXUS, Model Year: 1991, Model line: SC400, Model: LEXUS SC400 1991Pages: 4087, PDF Size: 75.75 MB
Page 2021 of 4087

FUEL SYSTEM
1. When disconnecting the high fuel pressure line, a largeamount of gasoline will spill out, so observe the following
procedures:
(a) Remove the luggage compartment trim cover.
(b) Disconnect the fuel pump connector.
(c) Start the engine, After the engine has stopped on itsown, turn off the ignition switch.
(d) Put a container under the connection.
(e) Slowly loosen the connection.
(f) Disconnect the connection.
(g) Plug the connection with a rubber plug.
(h) Reconnect the fuel pump connector.
(i) Reinstall the luggage compartment trim cover.
2. When connecting the flare nut or union bolt on the high pressure pipe union, observe the following procedures:
(Union Bolt Type)
(a) Always use a new gasket.
(b) Tighten the union bolt by hand.
(c) Tighten the union bolt to the specified torque.
Torque: 34 N Vm (350 kgf Vcm, 25 ft Vlbf)
(Flare Nut Type)
(a) Apply a light coat of engine oil to the flare nut and tighten
the flare nut by hand.
(b) Using SST, tighten the flare nut to specified torque.
SST 09631±22020
Torque: 30 N Vm (310 kgf Vcm, 22 ft Vlbf)
HINT: Use a torque wrench with a fulcrum length of 30 cm
(11.81 in.).
3. Observe the following precautions when removing and installing the injectors.
(a) Never reuse the O±ring.
(b) When placing a new O±ring on the injector, take care not
to damage it in any way.
(c) Coat a new O±ring with spindle oil or gasoline before installing±never use engine, gear or brake oil.
FI±14
±
EFI SYSTEM Inspection Precautions
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Page 2026 of 4087

FUEL SYSTEM
1. When disconnecting the high fuel pressure line, a largeamount of gasoline will spill out, so observe the following
procedures:
(a) Put a container under the connection.
(b) Slowly loosen the connection.
(c) Disconnect the connection.
(d) Plug the connection with a rubber plug.
2. When connecting the flare nut or union bolt on the high pressure pipe union, observe the following procedures:
(Union Bolt Type)
(a) Always use a new gasket.
(b) Tighten the union bolt by hand.
(c) Tighten the union bolt to the specified torque.
Torque: 15 N Vm (150 kgf Vcm, 11 ft Vlbf)
(Flare Nut Type)
(a) Apply a light coat of engine oil to the flare nut and tighten
the flare nut by hand.
(b) Using SST, tighten the flare nut to specified torque.
SST 09631±22020
Torque: 30 N Vm (310 kgf Vcm, 22 ft Vlbf)
HINT: Use a torque wrench with a fulcrum length of 30 cm
(11.81 in.).
3. Observe the following precautions when removing and installing the injectors.
(a) Never reuse the O±ring.
(b) When placing a new O±ring on the injector, take care not
to damage it in any way.
(c) Coat a new O±ring with spindle oil or gasoline before installing±never use engine, gear or brake oil.
4. Install the injector to delivery pipe and cylinder head as shown in the illustration. FI±15
EFI SYSTEM
± Inspection Precautions
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Page 2073 of 4087

INSTALLATION OF FUEL PRESSURE
PULSATION DAMPER
(See Components on page FI±35)
1. INSTALL FUEL PRESSURE PULSATION DAMPER (a) In sta ll two ne w ga ske ts, th e No . 1 fu e l pip e an dpulsation damper.
(b) Using SST, torque the pulsation damper.
SST 09612±24014 (09617±24011)
Torque: 41 N Vm (420 kgf Vcm, 30 ft Vlbf)
35 N Vm (350 kgf Vcm, 25 ft Vlbf) for SST
HINT: Use a torque wrench with a fulcrum length of 30 cm
(11.81 in.).
2. INSTALL STARTER (See page ST±5)
Torque: 39 N Vm (400 kgf Vcm, 29 ft Vlbf)
3. (A/T)
INSTALL DIPSTICK GUIDE FOR TRANSMISSION
(a) Install a new O±ring to the dipstick guide.
(b) Apply soapy water to the O±ring.
(c) Connect the dipstick guide end to the tube of the oil pan,
and install the dipstick guide with the bolt.
(d) Install the dipstick.
4. CHECK FOR FUEL LEAKS (See page FI±15)
FI±36
±
EFI SYSTEM Fuel System (Fuel Pressure Pulsation Damper)
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Page 2095 of 4087

4. VISUALLY INSPECT SPARK PLUGSCheck the spark plug for thread damage and insulator dam-
age.
If abnormal, replace the spark plug.
Recommended spark plug: ND PK20R11
NGK BKR6EP11
5. INSPECT ELECTRODE GAP
Maximum electrode gap: 1.3 mm (0.051 in.)
If the gap is greater than maximum, replace the spark plug.
Correct electrode gap of new spark plug:1.1 mm (0.043 in.)
NOTICE: If adjusting the gap of a new spark plug, bent
only the base of the ground electrode. Do not touch the
tip. Never attempt to adjust the gap on the used plug.
6. CLEAN SPARK PLUGS If the electrode has traces of wet carbon, allow it to dry and
then clean with a spark plug cleaner.
Air pressure: Below 588 kPa (6 kgf/cm2, 85 psi)
Duration: 20 seconds or less
HINT: If there are traces of oil, remove it with gasoline before
using the spark plug cleaner.
7. REINSTALL SPARK PLUGS Using a 16 mm plug wrench, install the spark plug.
Torque: 18 N Vm (180 kgf Vcm, 13 ft Vlbf)
8. RECONNECT HIGH±TENSION CORDS TO SPARK
PLUGS
(See steps 4 to 13 on pages IG±16 to 19)
IG±8
±
IGNITION SYSTEM On±Vehicle Inspection
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Page 2118 of 4087

SERVICE SPECIFICATIONS
SERVICE DATA
Oil pressureat idle speed29 kPa (0.3 kgf/cm, 4.3 psi) or more
at 3,000 rpm 294±539 kPa
(3.0±5.5 kgf/cm, 43±78 psi)
Oil pumpTip clearanceSTD0.310±0.490 mm0.0122±0.0193 in.
Limit 0.53 mm0.0209 in.
Body clearanceSTD 0.100±0.175 mm0.0039±0.0069 in.
Limit 0.20 mm0.0079 in.
Rotor clearanceSTD 0.030±0.090 mm0.0012±0.0035 in.
Limit0.12 mm0.0047 in.
TORQUE SPECIFICATIONS
Part tightenedN mkgf cmftVlbf
A/C compressor X Cylinder blockThrough bolt2626519
Bolt and nut 52530 38
Oil pressure switch X Cylinder
block14150 11
Oil drain plug X No.2 oil pan45450 33
Oil pump body cover X Oil pump
body10105 8
Plug X Oil pump body49500 36
Oil pump X Cylinder block21210 15
No.1 oil pan X Cylinder block12 mm head bolt21210 15
14 mm head bolt39400 29
Oil pan baffle plate X No.1 oil pan8.8 90 78 in.
Vlbf
Oil strainer X No.1 oil pan8.8 90 78 in. Vlbf
No.2 oil pan X No.1 oil pan8.8 90 78 in. Vlbf
Oil level sensor X No.1 oil pan5.4 5548 in. Vlbf
±
LUBRICATION SYSTEM Service SpecificationsLU±19
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Page 2119 of 4087

SERVICE SPECIFICATIONS
SERVICE DATA
Oil pressureat idling29 kPa (0.3 kgf/cm2, 4.3 psi) or more
at 3,000 rpm 294±588 kPa
(3.0±6.0 kgf/cm2, 43±85 psi)
Oil pumpTip clearanceSTD0.110±0.240 mm0.0043±0.0094 in.
Limit 0.35 mm0.0138 in.
Side clearanceSTD 0.030±0.090 mm0.0012±0.0035 in.
Limit 0.15 mm0.0059 in.
Body clearanceSTD 0.100±0.175 mm0.0039±0.0069 in.
Limit0.30 mm0.0118 in.
TORQUE SPECIFICATIONS
Part tightenedNVmkgf Vcmft Vlbf
Oil oumo body cover X Oil pump body101058
Oil pump X Cylinder block12 mm head 16160 12
14 mm head 30310 22
Engine speed sensor X Oil pump6.465 56 in. Vlbf
Oil filter bracket X Oil pump18185 13
Oil strainer X Oil pump7.880 69 in. Vlbf
Oil strainer X Cylinder block7.880 69 in. Vlbf
No.2 oil pan X Cylinder block10 mm head 7.880 69 in. Vlbf
12 mm head 18185 13
Oil pan baffle plate X No.1 oil pan7.880 69 in. Vlbf
No.2 oil pan X No.1 oil pan7.880 69 in. Vlbf
No.2 oil pan X Cylinder block7.880 69 in. Vlbf
Oil level sensor X No.1 oil pan5.45548 in. Vlbf
LU±20±
LUBRICATION SYSTEM Service Specifications
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Page 2123 of 4087

A pressure feeding lubrication system has been adopted to supply oil to \
the moving parts of this engine. The
lubrication system consists of an oil pan, oil pump, oil filter and other external p\
arts which supply oil to the moving
parts in the engine block. The oil circuit is shown in the illustration at th\
e top of the previous page. Oil from the
oil pan is pumped up by the oil pump. After it passes through the oil fi\
lter, it is fed through the various oil holes
in the crankshaft and cylinder block. After passing through the cylinder b\
lock and performing its lubricating func-
tion, the oil is returned by gravity to the oil pan. A dipstick on the center\
left side of the cylinder block is provided
to check the oil level.
OIL PUMP The oil pump pumps up oil from the oil pan and sends it under pressure to t\
he various parts of the engine.
An oil strainer is mounted in front of the inlet to the oil pump. The oil \
pump itself is a trochoid type pump, inside
of which there is a drive rotor and a driven rotor. When the drive rotor rotates, the driven rotor rotates in the same
direction, and since the axis of the driven rotor shaft is different from the center of the driven rotor, the space
between the two rotors is changed as they rotate. Oil is drawn in when the space\
is wide and is discharged when
the space in narrow.
OIL PRESSURE REGULATOR At high engine speeds, the engine oil supplied by the oil pump exceeds the\
capacity of the engine to utilize
it. For that reason, the oil pressure regulator works to prevent an over\
supply of oil. During normal oil supply, a
coil spring and valve keep the bypass closed, but when too much oil is being \
fed, the pressure become extremely
high, overpowering the force of the spring and opening the valves. This allow\
s the excess oil to flow through
the valve and return to the oil pump inlet.
OIL FILTER The oil filter is a full flow type filter with a built±in paper filter e\
lement. Particles of metal from wear, airborne
dirt, carbon and other impurities can get into the oil during use and co\
uld cause accelerated wear or seizing if
allowed to circulate through the engine. The oil filter, integrated into the oil line, removes these impurities as the
oil passes through it. The filter is mounted outside the engine to simplify\
replacement of the filter element. A relief
valve is also included ahead of the filter element to relieve the high oil pr\
essure in case the filter element be-
comes clogged with impurities. The relief valve opens when the oil pressure o\
verpowers the force of the spring.
Oil passing through the relief valve by±passes the oil filter and flo\
ws directly into the main oil hole in the engine.
±
LUBRICATION SYSTEM PrecautionsLU±3
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Page 2124 of 4087

PREPARATION
SST (SPECIAL SERVICE TOOLS)
RECOMMENDED TOOLS
EQUIPMENT
Part NameNote
Oil pressure gauge
Precision straight edgeOil pump
Torque wrench
LUBRICANT
Item
Capacity
ClassificationItemLitersUS qtslmp. qtsClassification
Engine oilAPI grade SG, Energy±Conserving II
Dry fill606353multigrade. Recommended viscosity is
Drain and refill6.06.35.3gy
as shown, with SAE 5W±30 being the
w/ Oil filter change 4.85.14.2preferred engine oil.
w/o Oil filter change4.54.85.3
g
SSM (SPECIAL SERVICE MATERIALS)
Part NamePart No.Use etc.
Seal packing or equivalent08826±00080Oil pump, Oil pan
Adhesive 1344,
Three bond 1344,08833±00080Oil pressure switch
Loctite 242 or equivalent
LU±4±
LUBRICATION SYSTEM System Circuit, Operation
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Page 2125 of 4087

OIL PRESSURE CHECK
1. CHECK ENGINE OIL QUALITYCheck the oil for deterioration, presence 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.
2. CHECK ENGINE OIL LEVELThe oil level should be between the ºLº and ºFº marks on the
dipstick.
If low, check for the leakage and add oil up to ºFº mark.
3. REMOVE ENGINE UNDER COVER
4. REMOVE DRIVE BELT Loosen the drive belt tension by turning the drive belt tension-
er clockwise, and remove the drive belt.
5. DISCONNECT A/C COMPRESSOR WITHOUT DISCONNECTING HOSES
(a) Disconnect the compressor connector.
(b) Remove the four mounting bolts and nut.
(c) R e m o v e t h e t h r ought bolt, and disconnect the
compressor from the engine.
HINT: Put aside the compressor, and suspend it.
6. REMOVE OIL PRESSURE SWITCH, AND INSTALL OIL PRESSURE GAUGE
(a) Disconnect the oil pressure switch connector.
(b) Using SST, remove the oil pressure switch.SST 09816±30010
(c) Install an oil pressure gauge.
±
LUBRICATION SYSTEM Oil pressure CheckLU±5
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Page 2126 of 4087

7. REINSTALL A/C COMPRESSOR(a) Install the A/C compressor with the through bolt, fourbolts and nut.
Torque:
Through bolt 26 N Vm (265 kgf Vcm, 19 ft Vlbf)
Bolt and nut 52 N Vm (530 kgf Vcm, 38 ft Vlbf)
(b) Connect the compressor connector.
8. REINSTALL DRIVE BELT Install the drive belt by turning the drive belt tensioner clock-
wise.
9. WARM UP ENGINE Allow the engine to warm up to normal operating
temperature.
10. CHECK OIL PRESSURE
Oil pressure:
At idle speed 29 kPa (0.3 kgf/cm , 4.3 psi)
or more
At 3,000 rpm 294±539 kPa (3.0±5.5 kgf/cm, 78 psi)
11. REMOVE DRIVE BELT (See step 4)
12. DISCONNECT A/C COMPRESSOR FROM ENGINE
(See step 5)
13. REMOVE OIL PRESSURE GAUGE AND REINSTALL OIL PRESSURE SWITCH
(a) Remove an oil pressure gauge.
(b) A p p ly a dhesive to two or three threads of the oil
pressure switch.
Adhesive: Part No. 08833±00080, THREE BOND 1344,
LOCTITE 242 or equivalent
(c) Using SST, install the oil pressure switch.
SST 09816±30010
Torque: 14 NVm (150 kgf Vcm, 11 ft Vlbf)
(d) Connect the compressor connector.
14. REINSTALL A/C COMPRESSOR (See step 7)
15. REINSTALL DRIVE BELT (See step 8)
16. START ENGINE AND CHECK FOR LEAKS
17. REINSTALL ENGINE UNDER COVER
LU±6
±
LUBRICATION SYSTEM Oil pressure Check
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