The heat is generated in engine due to combustion of air-fuel mixture that is why the Necessity Of Cooling In Internal Combustion Engine is required.This is done by air or water.Each cooling system has its own advantages and disadvantages,the most common defects occurring in water cooling system are,
01) Loss Of Coolant:-
Water leakage and water evaporation is the main cause of water loss from the cooling system.Water leakage may occur due to faulty head gasket,loose cylinder head,cracked head or engine block,loosening of hose clamps and radiator pipe leaks.
To stop such a leakage,head gasket may be replaced,hose clamp may be tightened and radiator pipe soldered.To compensate the loss of water due to evaporation can be done by filling the water at correct level in radiator.
02) Overheating Of Coolant:-
This is caused due to rusting,sealing of water jackets and radiator, defective hose,defective water pump,defective thermostat,slipping of fan belt,blocking of air passage in the radiator and loss of cooling water.
The heat transfer from the wall of the cylinder to the coolant is mostly effected due to rusting and scaling takes place on the walls.This may be removed by washing the cavities with ordinary washing soda or some other chemical and reverse flushing.
Sometimes worn out hose material goes into the water passage and accumulates there restricting the flow of coolant.Replace the defective hose at earliest.Repair defective water pump and replace defective thermostat Will solve the problem.The circulation of air is effected by slipping of fan belt.To remove this defect,tightened the fan belt as per requirement or replace if required.Remove the greasy material if found on pulley grooves.
Clean the radiator by blowing air under pressure from fan side.If there is loss of coolant due to any reason,the water must be filled in radiator up to required level without hesitation.
03) Over cooling Of Coolant:-
Over Cooling is generally caused by a thermostat that opens too early or remain open at all times.In some cases,it is observed that there is no thermostat employed or missing.If By-Pass valve remain open at all time,it results the over cooling of water.to avoid over cooling,the defective thermostat must be replaced and early action should be taken to close the By-Pass valve.
The circulation of water may be effected due to freezing of cooling water as it blocks the circulation passage.To overcome this problem,the engine must be run idle for some time until it attains the proper temperature.
04) Water Circulating Pump Noise:-
Water pump gives noise due to dry bearing or bushing,loose pulley on the pump shaft,loose impeller on the shaft etc.The proper cause of trouble may be found out and rectified.
05) Defective Temperature Gauge:-
If the temperature gauge on the panel is suspected to be giving incorrect readings the temperature of the cooling water be measured by inserting a thermometer in the radiator upper tank and then compared with the reading of the gauge.If the gauge is found defective it should be replaced.
There are may be some more defects which you know better than me,add it by comment.
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