
H
igh temperature (above 2200°C) caused by the running of engine will heat up the contacted parts (like cylinder head,
cylinder block, piston, piston ring, valve, etc) , thus reduce the mechanical strength of the above parts, cause distortion,
damage the normal clearance between parts, cause serious weariness, or even serious dislocation and cracks. High
temperature will also cause malfunction of lubrication oil, which will lower the co efficiency of air inlet and reduce engine
power. Adequate cooling to parts working under high temperatureconditions is an essential process to ensure the proper
MR6370 radiator belongs to tube and strap type. The structure is characterized by high radiation efficiency, light-weight,
easiness to manufacture, etc. The size of heat radiator adopted by MR479Q engine is shown on Table 16.
Chapter 10 Cooling System
1. Structure & Features of radiator
Section 1 Composition & Features of Cooling System
Fig. 316 Cycling Route of Coolant
Water pump
Cylinder
body cover
Cylinder
head cover
Ldle speed
valve cover
Thermostat
Lnner cycle
Outer cycle
A/c radiator
Radlator
function of the engine. However, it is important to
make adequate cooling. If being under-cooled,
malfunctions like reduction of inlet air volume, incom-
plete combustion, inflammation caused by knock,
surface inflammation, etc will occur. If being
overcooled, work temperature of lubrication oil will be
lowered, which will increase the vicosiity of lubricant.
The increase of lubricant viscosity will increase friction
to the contacted moving parts. Besides, the redundant
heat emitted by the running of engine will result in
condensation of vapor in the heated air and increase
acidity of air, both of which will add corrosion to the
cylinder. Also, the condensed gasoline vapor will
result in backflow of gasoline oil drop to the lubricant
sump, which will hazard the economy and power of
engine, increase the weariness and shorten its effec-
tive life.
Cooling system is designed to ensure adequate
cooling and working temperature for engine under any
possible working conditions. The diagram for the
circulated working process of cooling system is shown
on 316.
Closed forced water cooling system is chosen for engine. The system is composed of a radiator (water tank), a water pump,
a thermostat electric fan, a temperature controller and cooling pipes, etc.
143
Содержание JL481Q
Страница 1: ......
Страница 9: ...5 Fig 3 Components Assembly Drawing of MR479Q MR479QA Engine ...
Страница 10: ...6 Fig 4 MR479Q MR479QA Engine and Its Power System ...
Страница 11: ...7 Fig 5 Assembly Drawing of Engine and Its Auxiliaries MR479Q MR479QA ...
Страница 12: ...8 Fig 6 Electronic Control Fuel Injection System in Engine MR479Q MR479QA ...
Страница 13: ...9 Fig 7 Front view of Engine JL481Q MR481QA ...
Страница 14: ...10 Fig 8 Sectional elevation of Engine JL481Q MR481QA ...
Страница 15: ...11 Fig 9 Electronic Control Fuel Injection System in Engine JL481Q MR481QA ...
Страница 21: ...17 Fig 13 Exterior Feature of JL481Q Engine Power Me N m Torque Pe Kw ge g kwh Fuel Consumption Ratio ...