Cooling Systems Flashcards
Can you open a rad cap when the engine is hot?
No, can explode shooting coolant every where
Is coolant harmful?
Yes it is poisonous to animals and can also cause harm to groundwater supplies. Therefore coolant needs to be disposed of properly.
What are the functions of the cooling system?
- remove excess heat from the engine
- maintain a constant operating temperature under various driving conditions
- increases the engine to operating temperature as quickly as possible
- provide heat to the passenger compartment of vehicle
What is a typical engine operating temperature?
180F-210F
During combustion temperature can reach up to?
4000F (2484C)
What are two types of cooling systems?
Liquid cooling, air cooling
Describe how a liquid cooling system works.
Liquid (coolant) is used to absorb excess heat created during combustion. Coolant travels through the cylinder head and engine block to absorb heat and is then cooled off by the radiator.
Describe the air cooling system.
Large fins on the cylinders act as a heat sink, outside air cools the fins. Plastic or metal ducts direct outside air over the fins.
What are the advantages of using liquid cooling.
- more precise control of engine operating temp
- less engine temp fluctuations
- reduced exhaust emissions
- increased fuel economy
- ability to warm up the interior of the vehicle without use of electric heaters
Describe a water pump.
Usually driven by the timing belt or a drive belt. The water pump circulates coolant through the cooling system.
Describe the radiator.
An engine cooling device in a motor vehicle consisting of a bank of thin tubes in which circulating fluid is cooled by the surrounding air.
Describe the function of an electric cooling fan.
Pushes air through the radiator to aid in cooling at lower speeds or when idling.
Describe the upper radiator house.
Connects the radiator to the thermostat housing. Usually from a rubber impregnated reinforced cord.
Describe the lower radiator hose.
Connects the water pump to the radiator. Most lower hoses have a spring inside, to prevent the hose from collapsing due to suction created by the water pump.
Describe the heater core.
Warm coolant passes through the heater core to provide heat to the cabin of the vehicle.
Describe the thermostat.
Used in the cooling system to control the flow of coolant between the cylinder block and radiator. Helps warm the engine faster and maintain a proper operating temperature.
Describe the coolant recovery tank.
Collects the expanding coolant that is heated by the engine and recycles it back into the coolant system once it loses enough heat.
Describe the coolant temperature sensor.
Used to measure the temperature of the engine coolant. This info is then used by the engine computer for the fuel infection system and to know he to turn on the coolant fan and to aid in adjusting fuel volume.
Describe the radiator cap.
A pressure sealed cap located on top of the radiator. It allows the cooling system to operate under pressure (12-15psi).