Frequent washing is half the battle in keeping your car’s finish in prime shape. (The other half is protecting the paint from environmental deterioration with a good wax or sealant.) Washing a car seems like a pretty simple and straightforward process, right? You splash on a few suds and water, rinse it off, run a cloth over it and-voil-you have a clean car. It’s not unusual, however, for people to inadvertently harm their car’s finish when they wash it, because they don’t know the subtle pitfalls to watch for. If you really care about maintaining a perfect showroom shine, then here are some important rules that you might say are the commandments to wash by.
- …Never allow dead bugs, bird droppings, or tree sap to linger. These are mortal enemies of your car’s finish. If allowed to sit on the paint surface for any length of time, the high acidity of these elements can quickly seep into the paint, leaving scars in the finish that can only be removed by sanding and repainting. As soon as any of these elements appear on your car, wash them off; don’t wait to do it as part of a full wash.
If you live in a region that suffers from acid rain, it’s a good idea to rinse your car with clean water after rainy weather. When rain droplets evaporate, environmental acids can remain on the paint.
- …Never wash in direct sunlight. This is especially true on a warm or hot day. The sun heats up the sheetmetal, which in turn makes the suds and water dry much faster than on a cool, shade-protected surface. If soap dries on the paint, it can dull the surface. The other problem, especially in regions with hard water, is allowing the rinse water droplets to dry on the surface before you can wipe them off. When the water evaporates, it leaves minerals on the paint, creating water spots. To remove these unsightly marks the area needs to be rinsed again. On a more serious level, if hard-water spots are left on the surface for long periods of time, these also can eat into the paint and become difficult to remove. If you don’t have a shady area in which to wash the car, you can wait for a lightly cloudy day or wash the car when the sunlight is more diffused, such as in the early morning or at sunset. Even after the sun goes down, you’ll probably have at least 20 minutes of good light with which to wrap things up. Some detailers recommend washing the car in sections-wash and dry one section before moving on to the next, so that the water and soap are on the surface for less time.
- …Never use household detergents. This is one of the most common mistakes people make when washing cars. Many household detergents-including dish soap, laundry soap, and household cleaners-are too harsh to use on a car’s paint. They can strip off the protective wax coating and dull the paint’s surface. Only use car-wash products that are specially formulated to clean without taking off the wax.
- …Hose off loose or built-up dirt/debris. Before you lay a single soap bubble on the car, give it a thorough rinse. This does two things: It helps cool the sheetmetal, and it helps remove any loose or built-up dirt or debris. While scrubbing the car, loose dirt can be dragged across the paint surface, scratching it, so make sure you rinse the car well before applying a sponge or mitt to the surface. Dirt tends to build up along the rocker panels, in the wheelwells, and on other low-lying areas, so direct a strong stream of water at these parts to loosen and remove any grunge.
- …Never use abrasive material on the paint. Whether washing or drying, never use a cloth or other material with a surface that can leave hairline scratches. Most people use a large sponge to apply the suds, although many professional detailers prefer to use a lamb’s-wool mitt. The thick nap of lamb’s wool allows any loose particles that are picked up to be worked up into the wool, as opposed to remaining on the surface as is more common with sponges. Whichever you use, apply lots of suds to help keep the paint surface well lubricated.
- …Rinse out the sponge/mitt often. As you apply the suds to the surface and work around the car, be sure to rinse the sponge or mitt often. Use separate buckets, one to hold the soap and water mixture, and another with water only, for rinsing the sponge. This keeps dirt from getting mixed into the sudsy wash water. After rinsing the sponge, dip it in the soap bucket for a fresh batch of suds.
- …Remove any remaining road debris. Since car-wash formulas need to be mild enough not to strip the car’s finish, they usually aren’t strong enough to remove built-up road tar, grease, or similar residues. This is a job for a dedicated bug-and-tar remover. Because whatever you use to remove the gunk will get blackened, it’s best to keep a cotton cloth or sponge handy just for this duty.
- …Rinse the car thoroughly. It’s preferable to use a fine spray attachment for rinsing. Spray the water on at a low angle; this will form a sheet of water that better covers the body contours. If you’re washing the car in sections, this will also help keep spray from splashing onto the already dried areas. After hosing off the suds, observe the pattern of the water left on the sheetmetal. If it forms into droplets, that indicates that the wax or protective coating over the paint is likely in good shape. However, if the water remains spread out over the metal in a sheeting pattern, it could be time for a new wax application. Interestingly, nonwax protectants can be formulated to produce either a droplet or sheeting effect, but since most people expect to see water droplets after applying a protectant, manufacturers tend to formulate their products to achieve this effect.
- …Dry thoroughly. Most professional detailers use soft cotton cloths to dry cars (terry cloth or cloth diapers work well), but since wringing the water out of them isn’t very easy, have several on hand. A more practical option for the average car owner is to use a natural or artificial chamois. Either one will effectively dry the car, but a natural chamois requires more maintenance: It can’t be stored wet, and it becomes stiff when dry, needing to be remoistened before use. An artificial chamois will often absorb more water, is machine washable, and some types can be stored moist without mildewing. Another way to speed up drying is to use a special soft-rubber squeegee intended for car finishes.
- …Never forget to clean the wheels and tires. Because of road residue and brake dust that collects on the wheels, they’re often the dirtiest parts of the car. Use a separate cloth or sponge to clean the wheels and tires. If the residue is light, soap and water will usually clean them adequately. For more-stubborn grunge, use a special wheel cleaner, but be careful to choose one that’s appropriate for the type of wheels you have. When in doubt, pick one that’s labeled as good for all wheel surfaces.
Are Automated Car Washes Safe? Many people are concerned about putting their pride-and-joy through an automated car wash because the brushes used in these setups have a reputation for leaving hairline scratches behind. While this is a justifiable concern with brush-based systems, according to Larry Ebert, editor of American Clean Car magazine (a car-wash trade publication), most of the newer outfits use “scratchless” systems that clean the car either with heavy strips of nonabrasive, cotton-based cloth or with pressure-wash systems that have no physical contact with the car. Before you drop off your car, check into which type of system is used.
Under normal circumstances, both systems are considered safe for factory paint jobs. The wild card in the cloth system, though, is how well it’s maintained. If not properly cared for, the washers can pick up debris that can cause scratches. Unfortunately, there’s no way of knowing what shape a particular system is in, but image counts a lot; if the shop and general customer area are neat, clean, and well cared for, it’s more likely that the wash system also is well maintained.
For rinsing, many modern car washes are using ionized water, which helps prevent the formation of water spots. Automated washes are also usually very water efficient, using far fewer gallons of water than the typical home washer would use. In addition, many modern facilities use water recycling systems.