engine ISUZU TROOPER 1998 Service Repair Manual

00 Ð 4 SERVICE INFORMATION
Checkpoint Possible cause Correction
Engine stop
mechanismDefective fuel cut solenoid valve Replace the fuel cut solenoid valve
3. ENGINE TURNS OVER BUT DOES NOT START
FUEL IS NOT BEING DELIVERED TO THE INJECTION PUMP
Fuel Fuel tank is empty Fill the fuel tank
Fuel piping Clogged or damaged fuel lines. Loose fuel
line connectionRepair or replace the fuel lines
Retighten the fuel line connection
Fuel filter Fuel filter overflow valve does not close Repair or replace the fuel filter
overflow valve
Clogged fuel filter element Replace the fuel filter element or
the filter cartridge
Fuel system Air in the fuel system Bleed the air from the fuel system
Fuel feed pump Defective feed pump Repair or replace the feed pump
FUEL IS BEING DELIVERED TO THE INJECTION PUMP
Fuel Use of the wrong fuel Use the correct fuel
Water particles in the fuel Carge the fuel
Fuel system Air in the injection pump Bleed the air from the fuel system
Injection nozzle Injection nozzle sticking Replace the injection nozzle
Injection nozzle injection starting pressure
too low
Improper spray conditionAdjust or replace the injection
nozzle
Injection pump Defective fuel injection nozzle resulting in
the fuel drippage after fuel injectionReplace the delivery valve
Defective injection pump control rack
operationRepair or replace the injection pump
control rack
Injection pump plunger worn or stuck Replace the injection pump plunger
assembley
Injection pump drive shaft seizure or other
damageReplace the injection drive shaft
Injection pump governor spring seizure Replace the injection pump
governor spring

SERVICE INFORMATION 00 Ð 9
4. EXCESSIVE FUEL CONSUMPTION
5. EXCESSIVE OIL CONSUMPTION
Checkpoint Possible cause Correction
Engine oil Engine oil unsuitable
Too mauch engine oilReplace the engine oil
Correct the engine oil level
Oil seal and gasket Oil leakage from the oilseal and/or the
gasketReplace the oil seal and/or the
gasket
Air breather Clogged air breather Clean the air breather
Intake and exhaust
valveWorn valve stems and valve guides Replace the intake and exhaust
valves and the valve springs
Checkpoint Possible cause Correction
Fuel system Fuel leakage Repair or replace the fuel system
related parts
Air cleaner Clogged air cleaner element Clean or replace the air cleaner
element
Idling speed Poorly adjusted idling speed Adjust the idling speed
Injection nozzle Injection nozzle injection starting pressure
too low
Improper spray condition Adjust or replace the injection
nozzle
Fuel injection timing Fuel injection timing improperly Adjust the fuel injection timing
Injection pump Defective Delivery valve resulting is fuel
drippage after fuel injectionReplace the delivery valve
Turbocharger Air leakage from the turbocharger intake
sideRepair the turbocharger intake side
Defective turbocharger assembly Replace the turbocharger assembly
Valve clearance Valve clearance improperly adjusted Adjust the valve clearance
Compression
pressureBlown out cylinder head gasket. Worn
cylinder liner.
Piston ring sticking between the valve and
valve seatReplace the related parts
Valve spring Valve spring weak or broken Replace the valve spring

SERVICE INFORMATION 00 Ð 11
8. DARK EXHAUST SMOKE
Checkpoint Possible cause Correction
Air cleaner Clogged air cleaner element Clean or replace the air cleaner
element
Injection nozzle Injection nozzle injection starting pressure
too low
Improper spray conditionAdjust or replace the injection
nozzle
Fuel injection timing Fuel injection timing improperly adjusted Adjust the fuel injection timing
Injection pump Defective Delivery valve resulting is fuel
drippage after fuel injectionReplace the delivery valve
Excessive injection volume Adjust the injection volume
9. OIL PRESSURE DOES NOT RISE
Checkpoint Possible cause Correction
Engine oil Improper viscosity engine oil. Insufficient
engine oilReplace the engine oil
Correct the engine oil volume
Oil pressure gauge
or unit
Oil pressure indicator
lightDefective oil pressure gauge or unit
Defective indicator lightRepair or replace the oil pressure
gauge or unit
Replace the indicator light
Oil filter Clogged oil filter element Replace the oil filter element or the
oil filter cartridge
Relief valve and by-
pass valveRelief valve sticking and/or weak by-pass
valve springReplace the relief valve and/or the
by-pass valve spring
Oil pump Clogged oil pump strainer Clean the oil pump strainer
Worn oil pump related parts Replace the oil pump related parts
Rocker arm shaft Worn rocker arm bushing Replace the rocker arm bushing
Camshaft Worn camshaft and camshaft bearing Replace the camshaft and the
camshaft bearing
Crankshaft and
bearingsWorn crankshaft and bearings Replace the crankshaft and/or the
bearings

00 Ð 12 SERVICE INFORMATION
10. ABNORMAL ENGINE NOISE
Checkpoint Possible cause Correction
Fuel Fuel unsuitable Replace the fuel
1. ENGINE KNOCKING
2. GAS LEAKAGE NOISE
Exhaust pipes Loosely connected exhaust pipes. Broken
exhaust pipesTighten the exhaust pipe
connections
Replace the exhaust pipes Check to see that the engine has been thoroughly warmed up before begining the troubleshooting
procedure.
Fuel injection timing Fuel injection timing improperly adjusted Adjust the fuel injection timing
Injection nozzle Improper injection nozzle starting pressure
and spray conditionAdjust or replace the injection
nozzle
Compression
pressureBlown out head gasket
Broken piston ringReplace the head gasket or the
piston ring
Injection nozzles
and/or glow plugsLoose injection nozzles and/or glow plugs Replace the washers
Tighten the injection nozzles and/or
the glow plugs
Exhaust manifold Loosely connected exhaust manifold and/or
glow plugsTighten the exhaust manifold
connections
Cylinder head gasket Damaged cylinder head gasket Replace the cylinder head gasket
3. CONTINUOUS NOISE
Fan belt Loose fan belt Readjust the fan belt tension
Cooling fan Loose coling fan Retighten the cooling fan
Water pump bearing Worn or damaged water pump bearing Replace the water pump bearing
Alternator or vacuum
pumpDefective alternator or vacuum pump Repair or replace the alternator or
the vacuum pump
Valve clearance Clearance improperly adjust Adjust the valve clearance

00 Ð 14 SERVICE INFORMATION
Condition Possible cause Correction
Engine overheating Low coolant level Replenish
Thermo unit faulty
Faulty thermostat
Faulty coolant unit
Clogged radiator
Faulty radiator cap
Low engine oil level or use of improper
engine oil
Damaged cylinder head gasket
Clogged exhaust system
Loose fan belt
Excessive fuel injected
Improper injection timing
Injection timing improper
Faulty thermostat
Faulty thermostatReplace
Replace
Repair or replace
Clean or replace
Replace
Replenish or change oil
Replenish
Replace
Clean exhaust system or replace
faulty parts
Adjust
Adjust
Adjust
Replace
Replace
Thermo unit faultyReplace Engine overcooling
Too long engine
warm-up time
Adjust
ENGINE COOLING TROUBLE

SERVICE INFORMATION 00 Ð 15
ENGINE ELECTRICAL
Check if the battery is normal, then perform the following diagnosis.
STARTER DOES NOT RUN
CHECK BATTERY
CHARGING FAILURE OR LIFE
CHECK BATTERY
BATTERY IS NORMAL
CHECK TERMINAL CONNECTION
CONNECTION FAILURE
CLEAN BATTERY TERMINALS, AND RECONNECT
TERMINAL CONNECTION IS NORMAL
CHECK STARTER OR STARTER SWITCH
FAILURE
REPAIR OR REPLACE
TURN ON HEAD LAMP AND STARTER SWITCH
HEAD LAMP DOES NOT COME ON
OR IT IS EXTREMELY DARK
a) LACK OF BATTERY CHARGING
b) SHORT-CIRCUIT IN STARTER COIL
c) FAULTY STARTER PARTS
HEAD LAMP ILLUMINATES
a) DISCONNECTED STARTER CIRCUIT
b) DISCONNECTED STARTER COIL
c) FAULTY STARTER SWITCH

00 Ð 18 SERVICE INFORMATION
PINION MESHES WITH RING GEAR BUT
ENGINE DOES NOT RUN
CHECK GROUND CABLE
YESNO
REPAIR OR REPLACE
GROUND CABLE
FAULTY CONNECTION
OF BRUSH AND
COMMUTATORBURNED-OUT
MAGNETIC
STARTER SWITCHDISCONNECTION
OR DAMAGE OF
FIELD COILDISCONNECTION
OR DAMAGE OF
ARMATURE COILSLIP OF
PINION
CLUTCH
REPAIR OR REPLACE STARTER

00 Ð 20 SERVICE INFORMATION
MAIN DATA AND SPECIFICATIONS
GENERAL SPECIFICATIONS
Engine type
Camshaft type
Cylinder line-type
Number of cylinders
Bore x stroke
Total piston displacement
Compression ratio
Engine weight (dry)
Engine idling speed (Reference)
Compression pressure
Firing order
Injection timing
VALVE SYSTEM
Intake valves
Exhaust valve
Valve clearance at
Oil filter
Oil capacity (Original factory fill or rebuilt engine)
Oil capacity (Service change)
with filter change
without filter change
Oil cooler
Inter cooler
Turbocharger
Control method
Lubrication method
Cooling method
(mm)
(cc)
(to 1)
N (kg/lb)
RPM
open at:
close at:
open at:
close at:
cold
intake:
exhaust:mm (in)Diesel, four cycle water cooled inline
Overhead valve
Dry type
4
95.4 x 107
3,059
20.0
2353 (240/529)(4JG2-NA)
2597 (265/584)(4JG2-T)
750 (4JG2-NA)
720 (4JG2-T)
2940 (30/426)-200
1–3–4–2
1¡A.T.D.C (4JG2-NA)
T.D.C. (4JG2-T)
B.T.D.C. 24¡
A.B.D.C. 55¡
B.B.D.C. 54¡
A.T.D.C. 26¡
0.40 (0.016)
0.40 (0.016)
Full flow and bypass combined type
7.1 liters (6.3 US quarts)
6.0 liters (6.3 US quarts)
5.0 liters (5.3 US quarts)
Water cooled type
Air cooled type
Wastegate control
Pressurized control
Coolant cooled kpa (kg/cm /psi)-rpm
2

SERVICE INFORMATION 00 Ð 21
Engine Cooling
Starting System
Cooling system
Radiator
Heat radiation capacity
Heat radiation area
Front area
Dry weight
Radiator cap
Valve opening pressure
Coolant capacityCoolant forced circulation
(2 tube in row) Tube type corrugated
318 x 10 (76000)
15.63 (1.454)
0.309 (2.029)
83 (8.5/18.7 )
88.2~117.6 (0.899~1.199/12.78~17.05)
2.8 (2.46/2.96) J/h (kcal/h)
m
2 (ft2 )
m
2 (ft2 )
N(Kg/lb)
kPa(Kg/cm
2psi)
lit (Imp.qt./US qt.)
Coolant pump
Pulley ratioCentrifugal impeller type
1.2
Coolant total capacity
lit (Imp.qt./US qt.)8.6 (7.57/9.09)
6
Rating
Voltage
Output
Time
Number of tooth of pinion
Rotating direction (as viewed from pinion)
Weight (approx.)
No-load characteristics
Voltage/current
Speed
Load characteristics
Voltage/current
Torque
Speed
Locking characteristics
Voltage/current
Torque
Model HITACHI S14-03
V
kw
sec12
30
9
Clockwise
N (kg/lb)
59 (6.0/13.2)
V/A
rpm11/160 or less
3900 or more
V/A
N•m (kg•m/lb•ft)
rpm10.85/300
7.4 (0.75/5.4) or more
2000 or more
V/A
N•m (kg•m/lb•ft)3/1300 or less
26 (2.7/20) or more
11.5/120 or less
4000 or more
7.5/500
13 (1.3/9) or less
1400 or more
2/850 or less
16 (1.6/12) or more2.2 2.8DENSO ADR4G1

SERVICE INFORMATION 00 Ð 23
SERVICE STANDARD
Engine Mechanicalmm (in)
Parts Items Service standard
Cylinder
HeadCylinder head deck, and
exhaust manifold mating
surface for flatness
Cylinder head height
Hot plug depression
Hot plug installation
pressure0.05 (0.0020) or less
92.0 (3.6220)
—
44000-54000N (4500–5500
kg/9923–12128 lbs)
0.2 (0.0079)
—
0.02 (0.0008)
—Service limit Remarks
Cannot be
reground
Free height
Squareness
Spring tension 48.0 (1.8898)
—
294 (30/66.1) Valve
Spring47.10 (1.8543)
1.7 (0.0669)
257.9 (26.3/57.9) At installed
height
38.9 (1.5) N (lb)
Diameter of Valve stem
Valve and valve guide
clearance
Valve guide upper end
height (Measured from the
Cylinder head upper face)
Valve guide margin
Valve thickness
Valve seat contact
surface angle
Valve seat contact width7.946–7.961
(0.3128–0.3134)
7.921–7.936
(0.3118–0.3124)
0.039–0.071
(0.0015–0.0028)
0.064–0.096
(0.0025–0.0038)
13.0 (0.5118)
1.1 (0.0433)
1.34 (0.0528)
1.38 (0.0543)
45¡
1.7 (0.0669)
2.0 (0.0787) Valve
and
Valve
Guide7.880 (0.3102)
7.850 (0.3091)
0.200 (0.0079)
0.250 (0.0098)
—
1.6 (0.0630)
1.1 (0.0433)
1.1 (0.0433)
—
2.2 (0.0866)
2.5 (0.0984) IN
EX
IN
EX
IN
EX
IN
EX
Curvature — Push rod
0.3 (0.0118)