Page 948 of 6020
6B – 4 ENGINE COOLING
GENERAL DESCRIPTION
COOLANT FLOW
RTW 66ALF000101
The engine cooling system consists of the radiator, the water pump, the cooling fan, and the thermostat.
To quickly increase cold engine coolant temperature for smooth engine operation, the coolant is circulated by the
water pump and thermostat through the bypass hose and back to the cylinder body.
The coolant does not circulate through the radiator.
W hen the coolant temperature reaches specified value, the thermostat will begin to open and a gradually increasing
amount of coolant will circulate through the radiator.
The thermostat will be fully open when the coolant temperature reaches specified value. All of the coolant is now
circulating through the radiator for effective engine cooling.
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Page 949 of 6020
ENGINE COOLING 6B – 5
WATER PUMP
RTW 46ASF000101
A centrifugal type water pump forcefully circulates the coolant through the cooling system.
The water pump is not disassembled type.
THERMOSTAT
030RY00005
A wax pellet type thermostat is used.
The jiggle valve accelerates engine warm-up.
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Page 954 of 6020

6B – 10 ENGINE COOLING
WATER PUMP
REMOVAL AND INSTALLATION
Read this Section carefully before performing any removal and installation procedure. This Section gives you
important points as well as the order of operation. Be sure that you understand everything in this Section before you
begin.
Removal
1. Radiator Upper Hose 1) Partially drain the engine coolant.
2) Remove the radiator upper hose.
031R300003
2. Water Outlet Pipe
1) Disconnect the turbocharger-cooling pipe from outlet pipe.
2) Loosen the fixing bolt and remove the water outlet bolt.
3. Thermostat
Remove the thermostat from the thermostat housing.
Take care not to damage the thermostat.
4. Upper Fan Shroud
5. Fan and Fan Clutch 1) Loosen the fan clutch nuts.
2) Remove the fan together with the fan clutch. Take care not to damage the radiator core.
6. Fan Drive Belt and Pulley
1) Loosen the tension adjust bolt on the generator.
2) Remove the fan drive belt with the fan pulley.
030R300001 7. Water Pump
1) Remove the water pump bolts.
2) Remove the water pump.
030R300002
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Page 955 of 6020

ENGINE COOLING 6B – 11
Inspection and Repair
The water pump is not disassembled type.
Make necessary parts replacement if extreme wear or
damage is found during inspection. Should any of the
following problems occur, the entire water pump assembly
must be replaced.
・ Cracks in the water pump body
・ Coolant leakage from the seal unit
・ Excessive radial play or abnormal noise in the fan center
when rotate by hand
・ Excessive thrust play in the fan center (Standard play: less
than 0.2mm)
・ Cracks or corrosion in the impeller
Installation
1. Water Pump
1) Install the water pump with new gasket.
2) Tighten bolts and nuts to specified torque.
W ater Pump Bolt/Nut Torque N·m(kg·m/lb ft)
20 (2.0/14)
2. Fan Drive Belt and Pulley
1) Install the fan drive belt and fan pulley.
2) Apply tension to the fan drive belt by moving the generator.
3) Apply a force of 98N(10kg/22 lb) to the drive belt mid- portion to check the drive belt deflection.
Fan Drive Belt Deflection mm (in)
New belt: 4-7(0.16-0.28)
Reuse belt: 6-9(0.24-0.35)
030R300002
030R300001
3. Fan and Fan Clutch
1) Install the fan and fan clutch to pulley.
2) Tighten the nuts to specified torque.
Fan Clutch Nut Torque N·m(kg·m/lb in)
8(0.8/69)
4. Upper Fan Shroud
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Page 961 of 6020

ENGINE COOLING 6B – 17
Inspection and Repair
Make the necessary adjustments, repairs, and part
replacements if excessive wear or damage is discovered
during inspection.
Radiator Cap
Measure the valve opening pressure of the pressurizing valve
with a radiator filler cap tester.
Replace the cap if the valve opening pressure is outside the
standard range.
Valve opening pressure kPa (psi) 93.3
∼
∼∼
∼122.7 (13.5
∼
∼∼
∼17.8)
Cap tester: 5–8840–0277–0
Adapter: 5–8840–2603–0
Check the condition of the vacuum valve in the center of the
valve seat side of the cap. If considerable rust or dirt is found,
or if the valve seat cannot be moved by hand, clean or replace
the cap.
110RS006
Valve opening vacuum kPa (psi) 1.96 ∼
∼∼
∼ 4.91 (0.28 ∼
∼∼
∼ 0.71)
Radiator Core
1. A bent fin may result in reduced ventilation and overheating
may occur. All bent fins must be straightened. Pay close
attention to the base of the fin when it is being straightened.
2. Remove all dust, bugs and other foreign material.
Flushing the Radiator
Thoroughly wash the inside of the radiator and the engine
coolant passages with cold water and mild detergent. Remove
all signs of scale and rust.
Cooling System Leakage Check
Use a radiator cap tester to force air into the radiator through
the filler neck at the specified pressure of 196 kPa (28.5 psi)
with a cap tester:
• Leakage from the radiator
• Leakage from the coolant pump
• Leakage from the water hoses
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Page 965 of 6020

SECTION 6C
FUEL SYSTEM
TABLE OF CONTENTS
PAGE
Main Data and Specifications ....................................................................................... 6C - 2
General Description ...................................................................................................... 6C - 3
Fuel Flow.................................................................................................................... 6 C - 3
Fuel Filter and Water Separator ............................................................................... 6C - 4
Injection Pump........................................................................................................... 6C - 6
Injection Nozzle ......................................................................................................... 6C - 7
Fuel Tank...................................................................................................................... .. 6C - 8
Removal .................................................................................................................... 6 C - 9
Installation ................................................................................................................ 6C - 9
Fuel Gauge Unit ............................................................................................................. 6C - 11
Removal ..................................................................................................................... 6 C - 12
Installation ................................................................................................................. 6C - 12
Fuel Tube / Quick - Connector Fittings........................................................................ 6C - 14
Filler Neck .................................................................................................................... .. 6C - 16
Removal ..................................................................................................................... 6 C - 16
Installation ................................................................................................................. 6C - 16
Fuel Filler Cap................................................................................................................ 6C - 17
Injection Pump ............................................................................................................... 6 C - 18
Removal and Installation .......................................................................................... 6C - 18
Removal ..................................................................................................................... 6C - 18
Installation ................................................................................................................. 6 C - 21
Injection Nozzle (4JA1L) ............................................................................................... 6C - 25
Disassembly .............................................................................................................. 6C - 25
Reassembly ............................................................................................................... 6C - 26
Special tools .................................................................................................................. 6C - 37
FU
EL SY STEM 6C – 1
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Page 967 of 6020
FUEL SYSTEM 6C – 3
GENERAL DESCRIPTION
FUEL FLOW
RTW 66CMF000101
The fuel system consists of the fuel tank, the fuel filter, the water separator, the injection pump, and the injection
nozzle.
The fuel from the fuel tank passes through the water separator and the fuel filter where water particles and other
foreign material are removed from the fuel.
Fuel, fed by the injection pump plunger, is delivered to the injection nozzle in the measured volume at the optimum
timing for efficient engine operation.
NOTE:
1 If it find abnormal condition on the fuel injector, refer to section 6E ENGINE DRIVEABILITY AND EMISSIONS.
2 Do not contain "Additive for water drain" with fuel.
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Page 968 of 6020
6C – 4 FUEL SYSTEM
FUEL FILTER AND WATER SEPARATOR
As the inside of the injection pump is lubricated by the fuel which it is pumping, the fuel must be perfectly clean. The
fuel filter and the water separator remove water particles and other foreign material from the fuel before it reaches
the injection pump.
The water separator has an internal float. W hen the float reaches the specified level, a warning light comes on to
remind you to drain the water from the water separator.
A diaphragm type priming pump is installed at the top of the fuel filter. It is used during the air bleeding procedures.
(Except EURO III model)
RTW 36CLF000701
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