Serious leakage or inadequate water cooling system
Overheating due to serious leakage of engine cooling system lead to insufficient coolant occurs, can be directly observed through the diagnosis andtroubleshooting smoothly. When in operation, the engine cooling waterconsumption due to excessive overheating phenomenon, should be first radiatorwith water after the engine idling, check the radiator, water pump outlet and thecooling system of each part is leakage phenomenon, if there should be excluded.Whether there is water check crankcase oil, if the oil in water with the engineoverhaul. Check exhaust pipe for drainage phenomenon, if any, may be thecylinder gasket destroyed, the water jacket and the cylinder collusion, should repairand replace cylinder head gasket. There are 2 reasons for the engine capacity of water cooling system is lower than the standard capacity and overheating: one istoo much scale. The main appearance of cooling liquid engine in the long-termwater, with the increase in mileage, scale water wall and thermal contact with the cooling water pipe will gradually thickening, especially high temperature parts more,serious impact on the radiation effect of the radiator. The engine for powergenerated heat to dissipate in time and cause overheating. For too much scale,can choose the scale cleaning agent, in accordance with the operating instructionsof the get rid of scale. The two radiator is blocked by sundries. Radiator sludge,scale, cotton and other debris many, many core pipe is blocked, the actual capacity of the radiator is far lower than the standard capacity. Remove engine inside the debris, overheating can disappear.
Pump work abnormally
If the driving instructions discharging or charging indicator lights up while the engine is overheating, generally for water pump belt broken. If the technology ofwater pump belt tension is good, right, you can consider whether the pump fails,the cooling water cycle disruption caused the engine overheating. To diagnose thetouch method can then, symptoms specific to the engine and radiator temperature is very high, especially at the lower part of the lower temperature. In this regard, torepair or replace the water pump water pump.
Fault thermostat
This fault is mainly the thermostat main valve cannot open or thermostat card lagbetween the big and the small circulation, in addition to the thermostat aging, poor sealing of the expansion body leakage etc.. These faults will cause the engine temperature cooling water circulation is not smooth, the engine overheating. There are 2 kinds of inspection methods thermostat: one is to start the engine (enginespeed must J, open the radiator cap observation, if the low and high temperaturecooling liquid rolling phenomenon, as the thermostat was stuck in the big small cycle; if the low temperature, strong surface rolling is the thermostat card in thecirculation state; if the temperature reaches normal engine operating temperature,the liquid level is still calm, the thermostat can not open. Two is the thermostatheating inside the cold liquid and observe its opening temperature, full temperature and the main valve lift and other indicators are in accordance with the provisions. If there is any indicator is not up to the requirements should replace the thermostat.
When the ignition is not
The engine in use, with the extension of time, mechanical wear will gradually increase, the ignition timing has a gradually late phenomenon, coupled with somedrivers always worry about the ignition will first appear detonation, the oftenartificially delayed ignition time. Late ignition, combustion contact time of gas andcylinder wall is too long, resulting in engine overheating. In addition, the ignition distributor in advance device working poor or failure, will cause the engine ignition lateness. Therefore, regular adjustment of ignition timing and the ignition device isto ensure good working condition, it is necessary to prevent engine overheating.
Fan clutch side
A silicone oil fan clutch for automobile, if the engine overheating, should check the water temperature at 90 ~ 95 ℃ fan can achieve the full. Simple method for detecting is: in the high temperature makes the engine flameout, push the fan, orfeel laborious as normal, and will need to overhaul. The temperature controlelectric fan check (in Santana as an example): under normal circumstances, when the temperature reached 93 ~ 98 ℃, fans began to run at low speed; when the temperature rose to 99 ~ 105 ℃, fans began to high-speed operation. Otherwise,should replace the temperature control switch.
The influence of air conditioning
Some car in the same parts of the original case, installation of the air-conditioning system, the heat load of condenser on the radiator, and cause the engine overheating. In this regard, we should take the following measures: increase thefan size or the multi blade fan; the condenser position to be adjusted when necessary to install electric fan; diligent maintenance, regular cleaning blockageradiator, condenser fins, raise the heat capacity.
Special Yu professional fan clutch that besides the reason mentioned above, thecurrent overheating engine also should pay attention to the following partsinspection: a fan blade angle should be in accordance with the provisions; two is the fan blade is too small (mainly modified car), fitted with a fan guard ring; three is a 492Q type gasoline engine also should inspect the cylinder cover at the front end of the diaphragm pump inlet and outlet are corrosion collusion; four is the slidingperformance of the car is good
