check engine NISSAN PICK-UP 1998 Repair Manual

INSPECTION
Check fan coupling for rough operation, wobbling, oil leakage or
bent bimetal.
After assembly, verify the fan does not wobble or flap while the
engine is running.
WARNING:
lWhen the engine is running, keep hands and clothing
away from moving parts such as drive belts and fan.
Refilling engine coolant
For details on refilling engine coolant, refer to MA section
(``Changing Engine Coolant'', ``ENGINE MAINTENANCE'').
SLC072
SLC151B
ENGINE COOLING SYSTEMKA
Cooling Fan (Crankshaft driven) (Cont'd)
LC-11

Oil Pressure Check (On-vehicle service)
WARNING:
lBe careful not to burn yourself, as the engine and oil
may be hot.
lOil pressure check should be done in ``Neutral'' gear
position.
1. Check oil level.
2. Disconnect oil pressure switch harness connector.
3. Remove oil pressure switch.
4. Install pressure gauge and hose.
5. Start engine and warm it up to normal operating temperature.
6. Check oil pressure with engine running under no-load.
Engine speed
rpmApproximate discharge pressure
kPa (bar, kg/cm2, psi)
Idle speed More than 78 (0.78, 0.8, 11)
3,000294 - 392
(2.94 - 3.92, 3.0 - 4.0, 43 - 57)
If difference is extreme, check oil passage and oil pump for
oil leaks.
7. Install oil pressure switch with sealant.
Oil pressure switch:
:10-13Nzm (1.0 - 1.3 kg-m, 87 - 113 in-lb)
DLC013
DLC002
ENGINE LUBRICATION SYSTEMTD
LC-13

Oil Pump
OIL PUMP INSPECTION
1. Inspect pump body, gears and drive shaft for wear and dam-
age.
2. Using a feeler gauge and fuse wire, check the following
clearances.
Gear side clearance:
Less than 0.13 mm (0.0051 in)
Gear backlash:
Less than 0.43 mm (0.0169 in)
3. Measure inside diameter ``A'' of bushing.
A: 13.012 - 13.106 mm (0.5123 - 0.5160 in)
SLC020AB
SLC966
SLC967
SLC968
ENGINE LUBRICATION SYSTEMTD
LC-14

Oil Filter Bracket
OIL PUMP RELIEF VALVE INSPECTION
1. Visually inspect components for wear and damage.
2. Coat relief valve with engine oil and check that it falls
smoothly into the valve hole by its own weight.
If damaged, replace oil pump relief valve set.
OIL FILTER RELIEF VALVE INSPECTION
Inspect oil filter relief valve for rough movement and damage by
pushing the ball.
If damaged, replace oil filter bracket assembly.
DLC003
ENGINE LUBRICATION SYSTEMTD
LC-16

Oil Cooler
OIL COOLER RELIEF VALVE INSPECTION
Inspect oil cooler relief valve for movement, cracks and breaks
by pushing the ball.
If damaged, replace oil cooler relief valve set.
REGULATOR VALVE INSPECTION
1. Visually inspect components for wear and damage.
2. Coat regulator valve with engine oil and check that it falls
smoothly into the valve hole by its own weight.
If damaged, replace regulator valve set.
SLC141B
ENGINE LUBRICATION SYSTEMTD
LC-17

Cooling System Inspection
WARNING:
Never remove the radiator cap when the engine is hot; seri-
ous burns could be caused by high pressure fluid escaping
from the radiator.
Wrap a thick cloth around cap and carefully loosen it a quar-
ter turn to release built-up pressure. Then remove the cap
completely.
CHECKING HOSES
Check hoses for proper attachment, leaks, cracks, damage,
loose connections, chafing and deterioration.
CHECKING RADIATOR CAP
Apply pressure to radiator cap by means of a cap tester to see
if it is satisfactory.
Radiator cap relief pressure:
78-98kPa
(0.78 - 0.98 bar, 0.8 - 1.0 kg/cm
2, 11 - 14 psi)
Pull the negative pressure valve to open it. Check that it closes
completely when released.
CHECKING COOLING SYSTEM FOR LEAKS
Apply pressure to the cooling system by means of a tester to
check for leakage.
Testing pressure:
157 kPa (1.57 bar, 1.6 kg/cm
2, 23 psi)
CAUTION:
Use of pressure higher than the specified value may cause
damage to radiator.
SLC613
SMA967B
SMA990A
ENGINE COOLING SYSTEMTD
LC-20

Water Pump and Cooling Fan (Camshaft
driven)
REMOVAL AND INSTALLATION
Drain coolant from drain plugs on cylinder block and radiator.
Cylinder block drain plug
(Use proper sealant):
:20-29Nzm (2.0 - 3.0 kg-m, 14 - 22 ft-lb)
CAUTION:
lWhen removing water pump assembly, be careful not to
get coolant on drive belt.
lWater pump cannot be disassembled and should be
replaced as a unit.
lAlways replace with new gasket.
lAfter assembly, verify the fan does not wobble or flap
while the engine is running.
lAfter installing water pump, connect hose and clamp
securely, then check for leaks using radiator cap tester.
WARNING:
When the engine is running, keep hands and clothing away
from moving parts such as drive belts and fan.
SMA617C
SLC978-A
ENGINE COOLING SYSTEMTD
LC-21

INSPECTION
1. Check for badly rusted or corroded body assembly and vane.
2. Check for rough operation due to excessive end play.
3. Check fan coupling for rough operation, wobbling, oil leakage
or bent bimetal.
The water pump and fan coupling cannot be disassembled
and should be replaced as a unit.
SLC979
SLC244
SLC245
ENGINE COOLING SYSTEMTD
Water Pump and Cooling Fan (Camshaft
driven) (Cont'd)
LC-22

Thermostat
lAfter installation, run engine for a few minutes, and
check for leaks.
lBe careful not to spill coolant over engine compartment.
Place a rag to absorb coolant.
INSPECTION
1. Check for valve seating condition at ordinary temperatures.
It should seat tightly.
2. Check valve opening temperature and valve lift.
Tropical type Standard type
Valve opening tempera-
ture ÉC (ÉF)76.5 (170) 82 (180)
Valve lift mm/ÉC (in/ÉF)More than 8/90
(0.31/194)More than 8/95
(0.31/203)
3. Then check if valve closes at 5ÉC (9ÉF) below valve opening
temperature.
DLC007
SLC343
ENGINE COOLING SYSTEMTD
LC-23

Cooling Fan (Motor driven)
Electrical Components Inspection
COOLING FAN MOTOR
1. Disconnect cooling fan motor harness connector.
2. Supply cooling fan motor terminals with battery voltage and
check operation.
Cooling fan motor should operate.
If NG, replace cooling fan motor.
COOLING FAN RELAY
DLC009
DLC010
SLC143B
DLC011
ENGINE ROOM FAN MOTOR ELECTRICAL CIRCUITTD
LC-26