Overheating Cooling System Thermostat Cylinder Head Radiator Water Pump Head Gasket
Understanding automobile cooling systems
We are a society on the go. Americans are dependant on their automobiles and the bonding relationships that ensue. We either love cars or hate them. Driving on the highway, more and more, we see the downfalls in those relationships. Some break-ups are unforeseen, such as tire damaged by debris in the road. However, most can be prevented by basic maintenace.Automobiles (although some are electric) get ther power from internal combustion engines. These engines are encased by a water jacket, a series of passages or channels running thorough the engine blocks and cylinder heads, in which water can pass through to cool the engine. The coolant system is a constant cycle of water flowing through the engine. Engines need to maintain certain temperatures to operate at their peak performance, and obtain better fuel economy.The top of the engine has an intake manifold. This is where the engine receives gas and air. Located towards the front of the intake manifold is the water return port, with a large rubber hose connecting it to the top of the radiator. Inside the return port is a bimetal device called a thermostat (a valve that opens and closes allowing water to escape from the engine and return to the radiator). The thermostat is temperature sensitive, and individualized to each engine to maintain the optimum running temperature.The radiator, located in front of the vehicle, has a large number of evenly spaced copper or aluminum tubes. These tubes, running from the top to the bottom of the radiator, cools the water as air passes between them. The top of the radiator is simply called the top-tank. The tank has two inlet hoses and works on a vacuum system. The large inlet hose is where the water returns to the radiator from the engine. The smaller one leads to a plastic reservoir located on one of the inner fenders of the automobile, referred to as the overflow tank. The bottom of the radiator, or lower tank, provides cooled water back to the engine and feeds into the bottom of the water pump.Located on the front of the engine is a large metal cover, that protects the engines timing belt or chain, and also serves to house the water pump. The water pump is the heart of the cooling system. Driven by a belt from the crankshaft, it pushes water through the engine’s water jacket, to cool it. The water continues to flow until it reaches a higher temperature than required, after which the thermostat opens and allows water to escape and flow to the radiator.As water heats in the engine, it expands and builds pressure. The coolant system is a sealed system and has to allow for the expansion. The thermostat has a spring safety pressure valve that will allow water to escape. The radiator is already full, so the water pushed out of the radiator and into the overflow tank. This tank needs to be kept at the required level. Although the radiator sends hot water to it, the water can evaporate, thereby reducing the coolant level. When the engine is off and begins to cool the water will contract and pull the previously expelled water back from the overflow tank, maintaining the proper amount of water inside the water jacket. If the water level is not maintained and is empty, the radiator will suck air into the system. Then, steam can build in the water jacket once the engine is back in operation, and the building pressure can cause hoses to burst, or even cause the cylinder head gaskets to fail. These can be extremely costly repairs, repairs that could be avoided if the car is properly serviced, and maintained.Things to look for and prevent serious damages are easy to spot. If the car has a check engine light, it will come on to notify the operator of a low-fluid situation, be it oil or water. When it is time to purchase gas, always check under the hood and check the fluid levels. If while driving, the temperature light come on (even for a second) or the gauge moves to an unsafe position, and then returns to a safe area, this is a sign something is about to go out, and the car needs to be serviced. If ignored, serious consequences will ensue. Cars can talk to us, if we will listen and pay attention to what they are trying to tell us.
