O. L. T.

iTrader: (17)

Info Provided by Rich @ http://www.intellexual.net/faq.html#00

Restoring Cloudy Headlights:

To eliminate condensation in the headlights, remove the headlight assembly from the car. It is held in place by three 10mm hexnuts. Examine the headlight housing and find the fracture(s) or crack(s), usually in the black plastic backing piece. Thoroughly seal the fractures with a silicone glass sealant or hot glue. The condensation problem should be eliminated.

To remove the cloudy mildew build up on your headlight covers you will need 2000-grit sandpaper, a polishing compound, and water. It is recommended that you wrap the 2000-grit sand paper around a block or something flat and smooth so that your sanding work is clean and even. The mildew is most likely on the outside of the headlight covering so wet down the effected area and gently sand away the grime while flushing liberally with water. Continue sanding as need until the cloudiness is gone. Dry the heeadlight covers, apply a protective coat of polish or wax, and buff out any fine scratches you see. 3M rubbing compound can be used for more severe build-up.

To clean mildew or hard water stains from the inside of the headlight cover, you will need to remove the headlight housing from the car and open it up. The headlight cover, headlight shield, and headlight backing pieces are held together with a very strong, resilient adhesive. In order to break this adhesive bond, you will have to heat the adhesive material to the point where it softens up enough to seperate. Three methods exist to accomplish this: 1) the hot oven trick, (2) the hot water trick, and (3) the heat gun trick. The melting point of the backing piece is a few degrees above the melting point of the adhesive so it is critical that you monitor the process throughout. The safest method is the hot water trick due to its inability to melt the headlight backing piece. It can also be the messiest. The oven trick is probably easiest and quickest, and the risk of damage here is low if you know what you're doing.

The Hot Oven Trick: Preheat oven to 225 degrees Farenheit (107 Celsius). Take this waiting time to remove all loose pieces, such as metal clips, rubber nozzles, and screws, from the headlight housing. Keep oven on at 225 degrees---this temperature is lower than the melting threshold of anything on the headlight housing. Place headlight housing on a baking sheet in center of the oven (or distanced from the heat filaments). Heat for about 10 minutes. Remove and begin prying away at the seals with a flat, non-sharp straight edge such as a butter knife, ruler, or flat-head screwdriver. Work quick as the adhesive is constantly cooling and hardening. Work around the entire housing prying open a wedge between the seal. Repeat this process as many times as it takes for you to get a good gap between the cover and backing pieces. Once the two pieces seperate even slightly, the whole headlight housing will snap open with ease. The adhesive will get stringy like melted cheese off a slice of pizza. Press the stray strands of adhesive back into the seal groove and do not get this adhesive dirty or contaminated.

The Hot Water Trick: Remove all loose pieces, such as metal clips, rubber nozzles, and screws, from the headlight housing. Fill a bucket or tub--large enough to completely submerge the headlight housing--with boiling hot water (212º Farenheit, 100º Celsius). You can wrap the headlight housing in three garbage bags to keep them dry or you can submerge them in the water bare. Hold the headlight housing under water for 15-20 minutes. Remove and begin prying away at the seals with a flat, non-sharp straight edge such as a butter knife, ruler, or flat-head screwdriver. Work quick as the adhesive is constantly cooling and hardening. Work around the entire housing prying open a wedge between the seal. Submerge in a fresh new batch of simmering hot water for another 15-20 minutes. Remove and repeat the prying process. Repeat this process as many times as it takes before you can get a solid finger grip in-between the cover and backing pieces. At this point you want to pry open with as much brute force as you can. Once you find a weak point on the housing, exploit this weak point and continue working a larger wedge in it. Once the two pieces seperate even slightly, the whole headlight housing will snap open with ease. Press the stray strands of adhesive back into the seal groove and do not get this adhesive dirty.

The Heat Gun Trick: I have not tested this method out myself yet so I have no instructions for it .

t2d2

iTrader: (8)

My mechanic provided another DIY tip for cleaning up cloudy headlights: toothpaste and a brillo pad. That worked pretty well, but didn't quite get me all the way there, so I finished it up with 2000 grit wet sanding + polish, similar to the suggestions above. The end result is a remarkable improvement to like new condition.

Either method will probably get you to the same place, but this way requires less sanding, which in turn means less risk of over-sanding and damaging the lenses.

t2d2

iTrader: (8)

I actually prefer a circular motion, as it's less likely to bite too deep in any one direction.