Page 183 - Mechanic Diesel - TT

MECHANIC DIESEL - CITS

reaches the correct temperature, the thermostat opens and water is circulated through the radiator to cool the
engine.

3 Coolant Hose: Coolant hose or coolant pipe is used to connect the water pump to the radiator and the
radiator to the engine block. It is made of rubber and cotton threads. This hose pipe is tightened by hose
clamps. PVC is used to make hose pipes.

4 Water pump: Centrifugal type water pump is used in engines. It is located towards the front of the cylinder
block or head. The water pump fan is driven by a belt from the camshaft pulley. The Impeller is fitted at one
end of the water pump shaft. low gains the shaft is fitted with a bearing in the pump housing. A water seal is
installed in the pump to prevent water from entering the bearings and to prevent water leakage. When the
propeller rotates, it draws water from the lower tank of the radiator and delivers the water under pressure to
the engine block through centrifugal force.

5 Radiator pressure cap: Water boils at 100°C in normal atmospheric conditions. At the highest altitude,
atmospheric pressure is less and water boils at temperatures below 100°C. To increase the boiling point
of water, the pressure of the cooling system has to be increased. This system is pressurized Obtained by
sealing with a cap. Cooling loss due to evaporation can also be reduced by using a pressure cap. This allows

170
CITS : Automotive - Mechanic Diesel - Lesson 47 - 56