4TNV98 & 4TNE98 Diesel Engine
Section 1. General Service Information
11
Function of Cooling System Components
Components Functions
Cooling System
The TNV engine is liquid-cooled by means of a cooling system. The
cooling system consists of a radiator, radiator cap, engine cooling
fan, engine coolant pump,thermostat, and reserve tank.
Note that
all cooling system components are required for proper engine
operation. Since some of the components are application
specific, they must be carefully selected by an application
engineer. The application specific items are not part of the
basic engine package as shipped from the Yanmar factory.
Engine Cooling Fan
The engine cooling fan is driven by a V-belt which is powered by the
crankshaft V-pulley. The purpose of the engine cooling fan is to
circulate air through the radiator.
Engine Coolant Pump
The engine coolant pump circulates the engine coolant through the
cylinder block and the cylinder head and returns the engine coolant
to the radiator.
Radiator
The radiator acts as a heat exchanger. As the engine coolant
circulates through the cylinder block it absorbs heat. The heat in the
engine coolant is dissipated in the radiator. As the engine cooling fan
circulates air through the radiator, the heat is transferred to the air.
Radiator Cap
The radiator cap controls the cooling system pressure. The cooling
system is pressurized to raise the boiling point of the engine coolant.
As the engine coolant temperature rises, the system pressure and
the coolant volume increases. When the pressure reaches a preset
value, the release valve in the radiator cap opens and the excess
engine coolant flows into the reserve tank. As the engine coolant
temperature is reduced, the system pressure and volume is reduced
and the vacuum valve in the radiator cap opens allowing the engine
coolant to flow from the reserve tank back into the radiator.
Reserve Tank
The reserve tank contains the overflow of engine coolant from the
radiator. If you need to add engine coolant to the system, add it to
the reserve tank; not the radiator.
Thermostat
A thermostat is placed in the cooling system to prevent the engine
coolant from circulating into the radiator until the engine coolant
temperature reaches a preset temperature. When the engine is cold,
no engine coolant flows through the radiator. Once the engine
reaches its operating temperature, the thermostat opens and allows
the engine coolant to flow through the radiator. By letting the engine
warm up as quickly as possible, the thermostat reduces engine
wear, deposits and emissions.
Summary of Contents for D20G
Page 2: ......
Page 5: ...Specifications TORQUE SPECIFICATIONS SB2004E00 D e c 1 9 9 8 ...
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Page 138: ...Diesel Engine Engine System 124 NOTE The crankshaft must rotate freely by hand 02900058 ...
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Page 341: ...4TNV98 4TNE98 Diesel Engine Section 3 Engine 87 4TNE98 Engine Figure 6 1 ...
Page 423: ...4TNV98 4TNE98 Diesel Engine Section 4 Fuel System 169 Fuel System Components Figure 7 1 ...
Page 477: ...4TNV98 4TNE98 Diesel Engine Section 7 Starter Motor 223 Starter Motor Troubleshooting ...
Page 494: ...4TNV98 4TNE98 Diesel Engine Section 8 Troubleshooting 240 Troubleshooting Charts ...
Page 495: ...4TNV98 4TNE98 Diesel Engine Section 8 Troubleshooting 241 ...
Page 496: ...4TNV98 4TNE98 Diesel Engine Section 8 Troubleshooting 242 ...
Page 498: ...4TNV98 4TNE98 Diesel Engine Section 8 Troubleshooting 244 4TNE98 Engine ...
Page 499: ...Service Manual G424FE LP Engine G424F LP Gasoline Engine G20G G25G G30G SB4320E00 Jan 2008 ...
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Page 529: ...G424F FE Service Manual Chapter 2 Recommended Maintenance 29 ...
Page 534: ...G424F FE Service Manual Chapter 3 Engine Mechanical System 34 MAIN BEARINGS 0 50 UNDERSIZE ...
Page 584: ...G424F FE Service Manual Chapter 3 Engine Mechanical System 84 ...
Page 729: ...G424F FE Service Manual 229 Chapter 8 Basic Troubleshooting ...
Page 731: ...G424F FE Service Manual 231 Chapter 8 Basic Troubleshooting ...
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Page 820: ...Power Train System Operation 14 Hydraulic System ...
Page 822: ...Power Train System Operation 16 Hydraulic System ...
Page 824: ...Power Train System Operation 18 Hydraulic System ...
Page 826: ...Power Train System Operation 20 Hydraulic System ...
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Page 1023: ...A374081 01 ELECTRIC SCHEMATIC MODEL D20 25 30G EM0K2 EM0K3 Cummins B3 3 ...
Page 1024: ...A654030 00 ELECTRIC SCHEMATIC MODEL D20 25 30G EM0QM EM0QN Yanmar 4TNE98 Tier 3 ...
Page 1025: ...A604500 00 ELECTRIC SCHEMATIC MODEL G20 25 30G EM0QF EM0QG GM G424F Non Certi LP ...
Page 1026: ...A604510 00 ELECTRIC SCHEMATIC MODEL G20 25 30G EM0QH EM0QJ GM G424F Non Certi GAS ...
Page 1027: ...A604516 00 ELECTRIC SCHEMATIC MODEL G20 25 30G EM0QY EM0QZ GM G424FE Tier 3 LP ...
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Page 1059: ...Safety Section 29 Lean away from the direction of fall Lean forward ...
Page 1071: ...General Section 41 Typical Example Side Shifter Serial Number If Equipped ...