Car Maintenance 101

Learn about the nuts and bolts of car repair. And you always need the right tools for the job.

Turn, Turn, and Turn

Before attempting even the simplest mechanical work, you must know which way to turn nuts and bolts.

Almost every part on a car is attached with bolts. More than any other action, car repair work requires removing and installing bolts.

However, it's often difficult to know how to remove bolts – which way do you turn them? You can't use trial-and-error if the bolts are stuck tight. Badly corroded bolts may need significant force to loosen them – but do you have the confidence to know which way loosens and which way tightens? Many folks have trouble with twisting things on and off. The reason is not dyslexia; it's the flawed application of "clockwise" to turning threaded devices.

Clockwise Method

The rule for turning nuts and bolts most often cited is "clockwise to tighten." Unfortunately, this explanation is incomplete. The idea of clockwise and counterclockwise or right and left isn't good enough for turning nuts and bolts; it depends on which way you're looking. With nuts and bolts, it's possible to look at the "clock" from behind, especially if you're under a car on your back.

The basic rule for this method is clockwise to tighten. A nut twists onto a bolt in a clockwise direction. (This process is also true for household jars, bottles, and everything that uses a twisting fastening device.) But it all depends on which way you're looking. If you've ever had trouble twisting the threads of a garden hose onto a faucet, you may have already experienced this problem and didn't know it. You were probably looking down and twisting the hose up from below. For the clockwise method to work in this case, you'd have to lie on your back and look up at the faucet as you screwed it on. Then it would be clockwise to tighten.

The good news is that there's a solution: it's called the right-hand rule.

Right-Hand Rule

The right-hand rule is a foolproof method for knowing which way to turn a threaded device. This method really works, and it gives the beginners like you the confidence to turn the correct way every time. The right-hand rule uses the thumb and fingers of your right hand to indicate the correct direction to turn anything with threads. Not only does the right hand rule have universality, it's easy to learn.

This is how the right hand rule works:

1. Make a fist with your right hand and stick out your thumb, hitchhiker-style.
2. Point your thumb in the direction you want the nut, jar lid, or light bulb to move– in or out.
3. Your finger tips now curve in the direction you need to twist.

Remember: the right-hand rule works only with the right hand.

Nuts and Bolts

A nut, which is like a dough nut, fits over a bolt. A bolt is long and usually fits through several parts to hold them together. A nut tightens onto a bolt and squeezes parts together tightly.

There are many different sizes, shapes, and strengths of nuts and bolts. Nuts and bolts on cars are usually made of steel. Those used inside the engine and suspension are usually high-strength, or casehardened, steel. These extra-strong nuts and bolts are stamped on top with a special code. Always replace nuts and bolts with the same type as those you take off.

What makes nuts and bolts work are the circular grooves cut around the outside of the bolt and on the inside of the nut: the threads.

Threads

Bolts, nuts, and light bulbs all use threads for tightening, which use the concept of an inclined plane, or wedge, to give mechanical advantage. The pyramids of Egypt were built by sliding the stones up milelong ramps; workers couldn't lift the stones straight up, but they could move it up a gentle incline. The huge stones were quarried with wedges and shaped with chisels, all using the same principle as threads: the inclined plane. Threads use this principle to help tighten things; they are a ramp twisted around a shaft.

If you look carefully enough at the threads of the nuts and bolts on your car, you can figure out which way to tighten or loosen them just by looking. With careful inspection, you can also see damage to the threads (or perhaps unwanted dirt). Threads that are damaged or are being stripped often have metal shavings in their grooves. Train your car eyes to see threads.

Washers

Washers are almost always used with nuts and bolts. They're necessary to prevent nuts from vibrating loose (sliding down the ramp) and to spread the force of the smaller nut. There are four main kinds of lock washers:

• Slotted lock washers
• Star washers
• NyLoc (these are actually nuts with a built-in plastic washer
• Flat washers

Slotted lock washers, which are the most common type, use the sharp edge of the slot to dig into the metal and hold it and a nut in place. Star washers use the slightly twisted spikes of the star to dig into the metal. NyLoc washers, which are the most expensive type and can be used only once, use plastic to melt into the threads and hold the nut in place. Flat washers, which don't lock, are used only to spread the force over a greater area and to protect fabrics and plastic from the sharp edges of a nut.

Gaskets

Gaskets are used between metal surfaces to seal against leaks. The gasket seals leaks by squishing itself into all the little cracks and imperfections when parts are squeezed together. Gaskets seal water leaks, oil leaks, air leaks, sound leaks, and exhaust leaks. They can be made from cork, paper, rubber, soft metal, asbestos, and various combinations of the above. Gaskets are usually flat and almost always destroyed when the two metal surfaces that sandwich the gasket are separated. Leaks on your driveway are often the result of old cracked gaskets.

Slightly tightening the bolts can sometimes temporarily cure a leak. Replacing the gasket is usually required.

Tools

There's no such thing as a complete toolkit. Professional mechanics buy tools all the time, often from a traveling Snap-on Tool truck. Most mechanics have tool collections from many sources, accumulated over a lifetime; there's no good reason to ever throw out a usable tool.

Make a Toolkit

Start with a plastic fishing tackle box as a first toolbox. Get one with several shelves for neatly storing smaller tools. A good mechanic has a place for every tool. I recommend keeping your toolbox conveniently in the trunk.

Because of poor materials and workmanship, discount tools are a bad investment. Cheap tools don't fit correctly and often ruin the nut or screw you are working on. Sometimes they simply break.

We recommend Craftsman tools as medium-priced tools with a lifetime guarantee.

Garage sales, estate sales, and flea markets are the best places to start your own tool collection. Old tools are very often of excellent quality and can be purchased for pennies on the dollar at these venues.

Using Tools

Use tools carefully, gently, deliberately, and slowly. Think ahead and plan where your hand might go if you slip. Thoughtfully select the tool that is best for the job. Use a screwdriver that fits the screw. It should take more time to get the right tool and get ready than to actually take a part off.

Here are a few tips:

• Stand when you work, if possible.
• Hold a screwdriver close to the tip with your free hand. This really helps the tip from slipping out of the slot.
• Spray WD-40 on nuts and bolts the day before you start a job.
• Consider where your hand will go if a tool slips.
• Be patient and calm when things go wrong.
• Keep clean and organized.

What tools do you need? Which ones should you buy first?

Toolkit for the Car

One tool that always comes with a car is a jack for changing a flat tire.

Also included is a lug wrench for removing the large lug nuts that hold on the wheels. If yours is missing, try a wrecking yard for a car jack and/or this wrench.

Buying the necessary tools can be expensive. Here's a list of tools you might consider carrying in your car. Shop for tools at garage sales and everywhere you go. These tools are not only for you and your car, but also for other motorists who may need help.

In the Glove Compartment

The following tools should be in your glove compartment:

• Flashlight (small)
• Paper and pencil
• Tire pressure gauge (check tire pressure whenever you want)
• Extra fuses
• Knife
• Quarters

In the Trunk

You should have a flat tire kit, an emergency kit, tools, and spare parts in your car trunk.

The following should be part of the flat tire kit:

• Spare tire
• Jack and lug wrench
• Tire block (used against a wheel to stop the car from rolling)
• Jack stands (placed under the car after it's jacked up as a safety measure)

Put the following in your emergency kit:

• Flashlight (large)
• Fire extinguisher
• Flares
• Jumper cables
• Emergency reflector
• First-aid kit
• Blanket

The following tools should be in your trunk:

• Squeegee
• Glass cleaner
• Paper towels
• Screwdriver (s)
• Pliers
• Screwdriver
• Crescent wrench (to turn many different sized bolts and nuts)
• Vise grips (pliers that grip hard and lock in place)
• Duct tape
• WD-40 (a penetrating oil useful for cleaning and loosening nuts and bolts)
• Rags
• Car clothes
• Gloves (both leather and disposable rubber gloves are useful)
• Always carry the following spare parts:
• One quart of engine oil
• One gallon of water
• Brake fluid
• Extra windshield wipers
• Spare key (hidden)
• Fan or serpentine belt (even if you can't install it yourself, you'll have the right part for the mechanic to install)

Tools for Beginning Maintenance and Repair

Here are some basic tools to consider collecting to use for auto maintenance jobs.

• Combination wrench set (general-purpose nut and bolt turners)
• Oilcan (handy for lubricating small things that squeak)
• Funnels (necessary for adding various fluids)
• Needle nose pliers (handy for squeezing and holding small things)
• Hammer(s)
• Hydrometer (used for testing antifreeze in the cooling system)
• Hydrometer (used for testing a battery)
• Wire brush (handy for cleaning threads)
• Socket set and associated ratchet handle (the best tools for turning nuts and bolts)
• More screwdrivers and pliers
• Grease gun (used for lubricating steering and suspension parts under the car)
• Allen wrench set (these funny tools come in handy)
• Oil filter wrench (used exclusively for removing the oil filter)
• Triangular file (handy for reshaping damaged threads)
• Magnet on a stick

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