Headlight Clear Coat Damage Reduces Light Output

Cars and trucks with dull, cloudy, yellowed headlights. You see them all the time. Vehicles on the road, in parking lots and maybe in your own driveway. Because of damaged headlight clear coat, the headlights don’t put out as much light as they used to. They look bad. They make the vehicle look aged. There’s nothing good about them except for their creation of replacement headlamp sales, and the only folks who like that are those who sell replacement headlamps!

The headlamps in question are made from polycarbonate plastic (PC). During the 1980s, most car and truck manufacturers stopped producing headlights with glass and began using polycarbonate plastic because of its lightweight and that it can easily be formed into a variety of complex shapes for many different vehicle designs. Polycarbonate has the benefit of not breaking as easily as glass. But the downside is the dullness, cloudiness and yellowing that occurs as the headlamp ages.

Consequences of dull, cloudy, yellowed headlights

Appearance of headlamps is a cosmetic thing; the more important issue is safety. Drivers cannot afford any reduction in visibility. Consider that 50 percent of vehicle collisions occur at night and as determined by the Automotive Aftermarket Industry Association (AAIA), 26 percent of these collisions were caused by poor lighting.

Research done by the American Automobile Association (AAA) shows that dull, cloudy and yellowed headlights, on low beam, have reduction in light output of nearly 80 percent as compared to when they were new. In other words, deteriorated headlights may produce only 22 percent of the light of new ones! Making the road, other cars, pedestrians, deer, etc. 80 percent less visible at night. Now that’s scary.

Of note, AAA made these determinations by conducting research using an accredited laboratory to test headlights from two popular sedans that had been in service for about 11 years. Light output from the deteriorated headlights were compared against the light output of corresponding new headlights to quantify the amount of light reduction. All testing was done in accordance with Federal Motor Vehicle Safety Standard 108.

There are other consequences of dull, cloudy and yellowed headlights. While not as dire as the safety issue, there is a chance the diminished headlamps will earn you a fix-it ticket and fine issued by the police. Also, resale value of the vehicle can be negatively affected because of poor appearance. Plus, the owner might be a bit bummed the guy next to him has clearer headlights at the Saturday morning Cars and Coffee.

Causes

So, what causes polycarbonate plastic headlamps to deteriorate? There are several factors.

Polycarbonate headlamps are produced with a protective headlight clear coat to prevent scratching of the lenses and sunlight damage. However, exposure to sunlight breaks down the coating, which causes yellowing and clouding. Ultraviolet (UV) rays from the sun can also cause the lens to develop micro-cracks which speeds up the color change. The resulting discoloration significantly diminishes light output.

Another cause is gravel, road salt, and other debris that strike the headlamps as the car or truck is being driven. This wears down the headlight clear coat and creates pits and scratches which adds to their cloudy appearance.

When chemical pollutants in the air react with water vapor and oxidants, they form acid sulfuric and nitric acids. These acids fallout when it is raining or snowing. Known as acid rain, these acids etch the lenses and create cloudiness.

Polycarbonate lenses are porous and when heated by the bulb inside, and by the sun, they absorb minute particles of dust and debris through these tiny pores, which adds to the cloudiness. When light passes through the lenses, it is refracted from the particles and creates glare for oncoming drivers.

All of this contributes to dull, cloudy and yellowed lenses. In some cases, headlights can require maintenance within three to five years of use.

Can it be avoided?

There are ways damage to polycarbonate plastic headlamps can be mitigated. Avoiding UV exposure is at the top of the list. Park your car in a garage or at least in the shade. Face the car away from the sun when parking outdoors to reduce UV exposure.

Keeping your headlights clean from dirt and chemicals is important. Wash them at least every three months with car wash and a sponge. Early signs of yellowing can be removed by carefully polishing the headlights with a non-abrasive polishing medium and a microfiber cloth.

Can polycarbonate plastic headlights be restored?

Thankfully, if the polycarbonate headlamps aren’t too badly damaged there are options for economically restoring them, rather than installing new units. Consider a headlamp typically ranges $130.00 to $430.00 depending on whether it’s an OEM or aftermarket part.

Restoration of the headlamps starts by removing the oxidized outer layer where pits, cloudiness, and yellowing reside. This is typically done with a fine abrasive, like fine sandpaper or abrasive pad, until the damage is removed. In extreme cases a heavier abrasive is needed, which requires polishing with a compound to smooth the surface.

Once a headlamp is restored the lens surface needs to be sealed with a high-performance headlight clear coat. Otherwise, the surface will cloud over in short order. This is the new protective coating that’s replacing the failed factory coating. So, the headlight clear coat needs to be UV stable to handle sunlight while not yellowing. Or else it’s right back to yellowed headlights. The headlight clear coat also needs to be durable and flexible to handle impact from gravel and debris without chipping, cracking or peeling.

Headlight restoration is far more cost effective than headlight replacement. Professional headlamp restoration services are available. Do-it-yourself kits are available as well.

Which brings us to the KBS Coatings Headlight Restore Kit

The KBS Coatings Headlight Restore Kit has everything needed to restore 4 or more polycarbonate plastic headlight lenses. The Headlight Restore Kit represents quite a savings compared to the typical $130.00 to $430.00 cost of replacement headlights.

Included in the Headlight Restore Kit is KBS Klean, which is used along with the included scrub pad to clean the surface and remove oxidation, cloudiness and yellowing. KBS Klean is a powerful, concentrated, water-based cleaner that deeply penetrates and cleans surfaces without leaving harmful residues or emitting noxious fumes. This procedure properly prepares the surface for application of KBS Coatings DiamondFinish Clear.

DiamondFinish Clear is a moisture cured, crystal clear, one part urethane clear coat that is that is UV stable, durable and extremely tough. It can perform in the toughest environments without yellowing, cracking or peeling. Because of its Advanced Cross-Linked Coatings Technology, it performs extremely well as a headlight clear coat. This technology makes the coating both flexible and durable, so it is tough against chips and cracks and doesn’t have issues with delamination or flaking away from the surface. For a demonstration of DiamondFinish Clear’s flexibility and durability see our video.

DiamondFinish Clear is a single component (1K) coating, which means user-friendliness with no self-mixing of two parts and is applied with the included sponge brushes. Since the coating is self-leveling it leaves a beautifully smooth surface without brush marks. Note: Most headlight clear coats have issues with this.

Check out this demonstration of the Headlight Restore Kit.

Dull, cloudy, yellowed headlights affect both the safety and appearance of vehicles. It’s important to maintain polycarbonate plastic headlights to keep light output as close to original as possible and to keep the headlights looking clear and bright.

For more information on the KBS Coatings Headlight Restore Kit CLICK HERE.