Performing your own auto repair vehicle maintenance can be a money and time-saver, but mistakes can be devastating to your pocketbook. Below are three common mistakes made by do-it-yourself mechanics and how to prevent them in order to avoid doing expensive damage to your car:
Forgetting to fasten the oil drain plug
The oil drain plug is located at the bottom of the oil pan, which is typically near the bottom of your vehicle's engine. It allows you to drain used oil quickly and efficiently; however, mistakes made in fastening the drain plug can be frustrating, at best, or very costly, at worst.
A common mistake is forgetting to replace the oil drain plug after draining the used oil. It is easy to do if you are in a hurry, and even experienced do-it-yourselfers can forget if they get complacent because of familiarity with the process. Adding oil to a car with a drain plug removed will only end up in multiple quarts pouring on to the ground, costing you money and also damaging the environment. And, if you drive off without noticing the leaking oil, you could do a lot of harm to your car's engine.
An easy way to remember to fasten the drain plug is by setting it inside your oil funnel; its presence will serve as a reminder to fasten it before pouring new oil.
Putting too much water into the cooling system
Your car's cooling system includes the radiator, coolant hoses, water pump, engine block cooling lines and the coolant itself. Antifreeze is vital to your engine's well-being because it resists both boiling and freezing; its ability to remain a liquid at high temperature points permits your engine to operate at maximum efficiency and safety. Conversely, the coolant's low freezing point prevents it from freezing inside your radiator, hoses, and motor.
A mistake made by amateur mechanics is to replace drained or lost coolant with too much water. If you drain coolant from your car, whether it is for a routine flush of the radiator or for other reasons such as changing a coolant hose, you must replace it with the appropriate amount of coolant. Too high a concentration of water can lead to inadequate cooling when it turns to steam inside your car's system, and it can also result in burst radiators, hoses and other serious damage if it freezes.
The appropriate concentration is usually around 50% coolant, but always follow the directions in your owner's manual or manufacturer service guide regarding exact ratios. Measure the amount of coolant and water used, as guessing can have serious consequences should you be wrong. If you are unsure about the ratio of coolant-to-water in your system, you can use a coolant tester to measure its concentration. However, the safest choice is to drain all of your coolant and refill with fresh coolant and water.
Installing the wrong battery
As you are probably aware, cars of today are completely dependent upon sophisticated computers and electronic controls. These systems provide for maximum fuel economy, performance, and reliability. However, they are sensitive to electrical surges that can destroy a computer's circuitry. Replacing a battery in your vehicle with the wrong one can lead to expensive damage in your car's computer and electronics.
Car batteries come in a wide array of shapes and sizes, and they also have electrical contact points known as posts or terminals. Battery terminals are either positive or negative, and they can be top-mounted or side-mounted, depending on specific unit. Manufacturers indicate positive terminals by imprinting a plus (+) sign near the appropriate location. Likewise, negative terminals are marked with a negative (-) sign. They also will usually place a red cap or cover over the positive terminal, and they may also use a black cap for the negative terminal.
It is common to find two batteries that look identical except for the placement of the terminal. In addition, the manufacturer will of such batteries will often designate the companion battery with an "R" or other designation in the part number.
For example, battery number 123 may have a companion that is identical in every way except for reversed terminals, and that battery may be designated as 123R. It is vital that you match battery numbers in their entirety when selecting and installing replacements. Never assume that a partial match is sufficient. Also, before you install a battery in your car, be sure that the terminals match your battery cables.
Do not use the color of the battery cap as your sole indicator; caps can be switched around in the store or after you buy the battery. The only reliable method is to check for the imprinted plus or minus on the surface of the battery itself.