3. System-by-System Maintenance
Maintenance Systems
This lesson presents seven major automotive systems and describes the major maintenance considerations for each. Dividing car maintenance into systems helps to decrease the intimidation factor. The assignments for this lesson include several scientific tests to help make observations about your car's performance and to help you get started with some hands-on understanding of auto maintenance.
System 1: Engine
Put in its most fundamental terms, an engine creates spinning motion by harnessing the explosive forces of burning gasoline inside an engine. The force of the rapidly expanding gases is transformed into spinning motion, and it rotates the wheels by a complicated series of gears.
The most important part of engine maintenance is monitoring the engine oil level, and the second most important part is changing engine oil – usually after 3,500 miles. A visual inspection of your engine is also an important task that should be done every time you fill up with gas. Open the hood and take a look at it. Use your car eyes to find potential problems such as a tiny leak, a bulging heater hose, an unusual smell, or a new patch of oil on the side of the engine.
Checking the oil level with the dipstick is a chore you should do every time you fill up with gas. Carefully monitor and observe the condition of the oil on the dipstick from fill-up to fill-up. Wipe and spread the oil on a clean sheet of white paper. Be on the lookout for sudden changes in your oil. An example of a change is a darkening of the oil, which can indicate a breach in a valve stem or a cylinder. The appearance of a white milky substance in the oil, indicating water in the oil, can indicate a failing gasket in the cooling system. These conditions might manifest themselves in the oil weeks or months before the problem leaves you stranded at the side of the road.
Mechanics often feel the engine oil between their fingers. If the oil is even slightly gritty to the touch, it's past time for replacement.
System 2: Drive Train
A drive train is composed of a transmission and a differential, or a combination of the two called a transaxle. A transmission, which changes the spinning motion of the engine into a usable controlled force, is attached to the back of an engine. To the untrained eye, it might appear to be part of the engine itself. A differential looks like a metal watermelon located between the two rear wheels. The job of a differential is to transfer spinning force sideways to the wheels. If you don't see it, you probably have a transaxle, which combines the two and is used for front wheel drive systems.
Just as you check your engine oil, the fluids of the transmission, differential, and transaxle should be inspected regularly and changed at about 50,000 miles. Inspection of these fluids is more difficult than engine oil because not every car has a dipstick for the transmission, and most cars require you to climb underneath and remove a bolt to inspect differential fluid levels. Fortunately, you don't need to have them inspected nearly as frequently as your motor oil.
It's a good idea to go to a local service station to service this system.
System 3: Fuel System
A fuel system supplies an engine with an exact mixture of vaporized gasoline and air. Either a carburetor or a fuel injection system is used to make this mixture. The fuel injection system is usually computerized.
To maintain the fuel system, do the following:
- Change fuel filters and air filters, and inspect for fuel leaks with your eyes and nose: Use your manual for the location and replacement schedule of fuel filters.
- Record your gas mileage at every fill-up: Changes in gasoline mileage are a first indicator of fuel system problems.
- Observe the exhaust pipe smoke: What color is it? Is it white or black? Place a sheet of typing paper against the smoke coming out the exhaust pipe. Note the moisture, oil, and the amount of carbon particles that collect. This analysis establishes a base level for analyzing your exhaust smoke.
- Observe the way your car idles: Open the hood and listen while your car is running. Is the idle steady with a nice purr, or does it speed up and slow down?
System 4: Cooling System
A cooling system maintains a constant engine temperature. This system includes the radiator, the hoses leading from the engine block to the radiator, a water pump attached to an engine belt, and a complex configuration of hoses leading to and from heaters and defrosters.
Maintenance involves often checking the radiator coolant level. Many modern engines have a plastic coolant overflow bottle, and you can readily see the coolant level by checking this bottle. A few older vehicles, however, require you to take the radiator cap off in order to peek inside and/or add fresh coolant.
This procedure should be done only while the car engine is cold to the touch.
In addition to checking the coolant level, it's important to inspect hoses for cracks, bulges, or leaks– especially around the hose clamps. These hoses are rubber and are not meant to last more than a few years. Unfortunately for motorists, hoses tend to fail suddenly. You may be driving along when you hear a hissing sound and see white steam coming from your engine compartment. The best maintenance for hoses is to replace them regularly before they fail – every two or three years.
A note on coolant: If you have a leak of yellowish-green, sickly sweet-smelling coolant, it can be a danger to cats and dogs. They like to drink it, and it can be fatal. Coolant spilled from a radiator should not simply be left on the street.
System 5: Running Gear
The running gear of a vehicle includes the parts that guide a car through bumps, fast turns, and hard stops. The steering, suspension, and tires comprise the major sections of this system. The running gear connects a driver to the road. Problems here often show themselves during hazardous driving conditions.
To maintain the running gear system, do the following:
- Pay attention to the way your car handles: When you drive over a bump, does it take a long time to stop bouncing? You may need new shock absorbers.
- Check the condition of your steering: Is the steering sloppy? Greasing the steering gear might help.
- Check for tire wear: Are your tires worn and frayed on the sides? Is the tire tread evenly worn? Is one tire always low on air? Is the tire tread wearing thin?
- Check the power steering fluid level.
The most important maintenance you can do on your running gear is to keep all four tires filled to the maximum allowable pressure, (the pressure number is clearly printed on the sidewall of every tire). You may have to get down on your hands and knees to read the pressure, however. Maintaining the maximum tire pressure decreases tire wear, increases gas mileage, and allows your suspension and braking systems to operate as they were designed to do.
System 6: Brake System
A braking system controls how fast, how smooth, and how straight a vehicle slows down. There are two types of braking systems: disc brakes and drum brakes. Many cars have both: disc brakes on the front wheels and drum brakes on the rear. Brakes work by pressing fibrous pads against a spinning metal surface. This process happens just behind each wheel.
When you press a brake pedal, a balanced force is directed to each of the four wheels. Each wheel must receive the same braking force, or else one wheel slows down more than the others and causes a car to pull. If your car is pulling to the left when you put on the brakes, the problem is probably on the left side. To maintain the braking system, do the following:
Check the hydraulic fluid level on a regular basis. A drop in fluid level indicates a leak. Inspect for fluid leaks on the back sides of all four wheels and under the wheels. Pay attention to the way your brakes work. Does the car pull to one side?
The assignments for this lesson include brake tests under driving conditions to observe the condition of your brakes.
System 7: Electrical System
The parts of an auto electrical system include a battery, a starter motor, an ignition key, an alternator, and an onboard battery charger.
The most common way you interact with your car's electrical system is when your battery goes dead. Rarely does a battery go completely flat without showing a few weak starts beforehand. Pay attention to the way your car turns over and starts.
Many batteries have plastic covers on top for checking and adding battery water. The most life you can expect from a battery is two or three years. Make a note of when you last replaced your battery, and keep your receipt and paperwork. If you have a dead battery, take it to the store where you bought it, and ask whether there's any warranty left. Take your paperwork, and smile broadly.
It's good preparation to carry an extra set of fuses in your car and to know where your fuse box is before you need to. Carry a flashlight in your car; you can see melted fuses much more easily. There are several types of fuses – which kind does your car use?
Use a dealership parts department for fuses and light bulbs. There are many variations, and your local parts store is probably not as knowledgeable about the specific fuse and bulbs types you may need as spare parts.
Moving On
In this lesson, you found out about the seven main parts of an engine. In Lesson 4, you find out how to perform some basic auto repair tasks.