The Cooling System

    cool flowWhen an engine runs, it creates massive amount of heat. The internal combustion temperatures often reach as high as 4500 degrees. The cooling system must prevent the engine from overheating—even if the out door temperature is 110, degrees in the shade. Without proper cooling, the engine would eventually burn and score its pistons, and warp or burn its valves and cylinder heads. Without its cooling system, the engine block would become a red-hot mass of molten metal. And excessive heat also can break down engine oil to the point where it fails to lubricate properly.

    It’s the job of the cooling system to maintain the engine at its most efficient operating temperature, at all engine speeds and under all engine loads/driving conditions.

    Paradoxically, the cooling system also keeps your engine warm. On a cold day, some engine parts might never warm to operating temperature without the cooling system. A cold engine is inefficient. Moreover, combustion gases leaking past the piston rings condense in the crank case, where they form acids and sludge that can be harmful to vital engine parts. Heat from the cooling system helps vaporize and eliminate those blow-by gases.

    Here is how a typical liquid cooling system works: A belt-driven centrifugal water pump circulates coolant—water plus antifreeze—through a water jacket that surrounds the engine’s combustion chambers. The coolant absorbs heat from the engine and then is pumped through the radiator.

    When the car is moving, outside air rushes through the grille and past the radiator cooling tubes and fins, drawing heat from the coolant. When the engine is idling or the car is moving slowly, a fan, powered by the engine through the fan belt/timing belt or electric fan assembly, provides a sufficient flow of air. Sometimes, the fan has a shroud to draw air through the radiator.

    A lot of people forget that it is air that actually does the cooling of the engine. The modern cooling system is designed to incorporates air flow dynamics in a more critical manner. The engine and its components are designed in a more temperature sensitive manner. Any changes to the air flow can create large changes to coolant temperatures. So, make sure that all the baffles and shrouds that was design for the vehicle are in place and unobstructed.

    A temperature-sensitive valve or thermostat, placed in the coolant outlet passage, controls the flow of engine coolant, provides fast engine warm-up and regulates coolant temperatures. When the coolant is cold, the valve remains closed. Because this prevents coolant from circulating through the radiator, the coolant in the engine circulates within the block and warms quickly. As coolant temperature rises, the valve opens to allow coolant flow into the radiator, where the heat is dissipated through the radiator walls to the surrounding air..

    Even when the thermostat is closed, the engine still needs swift circulation of coolant through its water jacket to prevent hot spots — small areas that get hotter than the surrounding metal. Coolant circulation is then passed through a bypass, sometimes a short length of hose from the thermostat housing to the water pump intake. Many modern engines has a built in bypass in the block assembly.

    When the car heater is turned on, it also works as a bypass circuit, tapping hot coolant from the top of the water jacket and feeding it back to the intake side of the water pump. The heater uses engine coolant heat to warm the incoming air; that is why it does not work well until the engine warms up. Air cooled engines uses a set of baffles to draw heat from the external part of the engine to warm the passenger compartment.

    As coolant is heated, it expands in volume. The use of a coolant recovery system permits this fluid expansion to overflow into the recovery reservoir. When the engine cools, the coolant contracts in volume and vacuum draws any that has overflowed into the bottle or reservoir back into the radiator. This assures that the radiator will not boil over, and so remain filled to capacity at all times, maintaining the specified level of cooling efficiency.

    cool system


    The Electrical System

    If you enjoy solving puzzles, you probably will enjoy curing your car’s electrical problems.

    car’s electrical wiring system starts at battery and reaches to all parts of the car. The ignition system, the starting system, and the charging system are parts of it.
    We will be looking into the basic wiring harness, test procedures, and horns and buzzers.

    With minor variations, all cars are wired the same. Heavy battery cables serve the starting circuit; the charging system wiring and the car’s electrical wiring system are attached to these cables. The wires are wrapped together into a harness for neat ness and protection. From the’ harness, wires branch off toward the ignition switch, charging system regulator, and other electrical components. You rarely need to cut into the wiring harness to cure an electrical problem.

    Wires are color-coded to help you trace them throughout the car. Sometimes, having the car’s wiring diagram is helpful when you work on an electrical problem. Though the diagram usually does not show the actual wire routings, it does indicate wire color-coding.

    Lights and accessories branch off this routing. Their supply wires fasten to them through terminals and sockets. Any troubles traced to these componencal system in the modern Carts are usually solved by replacing bulbs or repairing or replacing motors. ;

    The ground circuit is the final part of a car’s electrical wiring. Unlike house wiring, which comprises a “hot” wire to feed power and a white neutral wire to complete the circuit, car wiring completes most circuits through the car body, frame, ground cable, and back to the battery. That is called the ground circuit. Nearly every light, relay, motor, and solenoid is grounded to the car’s body or frame to complete its circuit.

    Poor grounding is a common source of auto electrical troubles. If the ground circuit is incomplete somewhere along the line, the circuit will fail just as though its insulated feed wire had been cut. Ground circuits fail through loosening and corrosion of fastenings. Continuity of the ground circuit must be considered when ever looking for an electrical malfunction. Fortunately, it is an easy check.

    In today’s auto advancements, it would be a good idea to acquires an extensive knowledge of electronics. You have to troubleshoot everything from control modules to sold state relays

    Autobody Basics and what tools needed

    Repairing a wrecked car can be either easy or difficult, depending entirely upon how stubborn the mechanic wants to be. He can think it through first, considering the point of impact, direction of force, method of repair, etc. — and he will save many hours of hard labor. Or he can leap into the repair on a purely mechanical scale, letting one foot follow the other — and he will spin his wheels unnecessarily. Learning to think about the job is just as important as learning the skills involved. While this site is not intended as a step-by-step experience in body straightening procedure, we will cover enough of the material to give the automotive enthusiast a good grounding in fundamentals.

    To the junior body man, whether he plans on making a simple repair or an extensive modification, the question of just how big a job to tackle invariably crops up in the light of reality after the initial glow of enthusiasm subsides. It is one thing to dream of building a radical custom or restoring a damaged car, and quite another to actually do the work successfully. Still, because body work is a step-by-step proposition, whether straightening a fender or making a custom grille, the average enthusiast can expect to achieve at least acceptable results if he plans well and takes time with the work. Unlike building a high-performance engine, the hot-rodder chopping a top can see immediate results as he progresses.

    There is much that can be learned about a damaged panel during the initial inspection, and the following hints will apply to all types of collision damage. First, locate the point, or points, of initial impact. Then decide if there are two or more points of impact. It so, are they equal or is there a significant major impact point with others secondary? How are the secondary areas of impact related to each other, and will repair of any area be related to the others. Should any specific area be repaired first? When looking at a collision damage, categorize the type of damage involved (buckles, displaced metal, etc. and then decide how each will be best repaired.

    The next step is to decide what tools and equipment is needed. Will you sub-contract some of the work. When it comes to frame work and painting, it is usually a good idea to let the pro’s handle that end of it.You might be able to handle some frame horn damage or light spot paint repairs. The heavier work takes more advanced equipment the home hobbyist wouldn’t have. I will try to give you an idea what materials and techniques are in the trade