Cleaning headlights

[JosephP]

That's a lot of tape Neil!  I assume to avoid the overspray from a gun.  Would you have used that much with a rattle can?

So from Rock Auto I can buy TYO brand (NSF/CAPA Certified - if that matters) replacement lenses for $85 and $89.  (OEM are +/- $250 each).  Not much money, and it doesn't LOOK like it is that hard of a job...  I'd probably spend as much time putting that much tape on


Will I be disappointed with the quality if I do that?  Am I better off cleaning what I have?*  Would you put the 2K aerosol on new lenses (before installing)?

*Caveat:  Before I bought the vehicle, it was involved in a minor deer collision so one of the lights has been replaced.  It looks good now, but I figured I'd do both so they are identical matches over time.

There are others on Amazon for $132 for the pair, but a handful of complaints about moisture in them.  They say they are "DOT and SAE" certified.

[MarkSingleton]

How many vehicles then, are on the road with headlights/taillights that are degraded?

A lot. And over time, a lot more.

From a public safety and common sense standpoint, why do we make them in such a
way that they will all end up degraded?

[JosephP]

....

From a public safety and common sense standpoint, why do we make them in such a
way that they will all end up degraded?

To save weight (compared to glass) to meet CAFE standards.

- oh sorry, you asked from a common sense standpoint. I don't think there is an answer.

[Willyou]

Anybody old enough to remember sealed beam headlamps? Glass lenses never had hazing problems. And, they were pretty inexpensive and easy to replace when needed. I guess the glass was considered a hazard and they weren't as stylish.
I'm being facetious, of course.

[greatscott]

If you have a spray gun:

First, if any of the damage to the headlamp is on the inside of the lens... you're toast. But you'll never now till you fix the outside. The inside damage isn't too common but I do see it. Mostly on the Mitsubishi and Chrysler products.

OEM headlamp lenses are coated with a clear UV resistant topcoat. When the topcoat fails, the sun eats away the poly-carbonate and it oxidize. So to really fix them, you need to sand off the oxidization, sand out the damage to the poly and apply a new topcoat.

First, I clean the lens with a solution of ammonia and water. I use the cheap yellow ammonia. Never use solvents on poly lenses or you'll never get it right. It will soften the lens making it near impossible to sand and it will push the stained yellow mess from sanding into any fissures and you can't get it out.

Then I tape off around the lens to insure I don't scratch the paint with my sand paper. Depending on how deep the damage is dictates which grit I start with. WET-SAND every step. If 600 grit doesn't cut it, I'll go to 400 and if it still doesn't cut it, I'll go to 240 grit. It's rare that I have to use 240.Sometimes I can get away with starting with 600 grit if the lens isn't eaten away too badly.  ALWAYS use a sanding block, fingertips aren't flat and you'll only have a few small points of sand paper contact. I use the black side of the Motor-Guard soft block for all my wet-sanding.

Not only are you sanding off the failed topcoat, you are sanding down to the bottom of any pitting in the poly. So I work my way down from the coarse grits to the finer grits. 400-600-800- and then finish off with 1500. I've stopped at 800 before and it will do in a pinch but still doesn't look like a new lens when done. 1000 or 1200 would probably do just fine but I don't stock it. 

Then I clean again with the ammonia solution and wash it off with water and a tiny little bit of dish soap, maybe 2 drops of dish soap in a quart of water. Then I rinse it off with clean water.

Once dry, I mask off around the lenses and shoot a 2 part automotive clear-coat over the lens. Looks like new and will last a lifetime. It's a better topcoat than what's applied by the manufacturer.

Thanks for putting this step-by-step together.  I'm going to do this to my truck headlights this weekend.  I'll post before/after pictures here.

[Stwood_]

Anybody old enough to remember sealed beam headlamps? Glass lenses never had hazing problems. And, they were pretty inexpensive and easy to replace when needed. I guess the glass was considered a hazard and they weren't as stylish.
I'm being facetious, of course.

I still have 2 trucks with sealed beams.  About 8 bucks each to replace one.

[MarkSingleton]

Sealed beam headlights in my '77 FJ40 Land Cruiser.

They don't put out anywhere near what my 2010 Tundra
does of course. But then, I don't drive it much at night.

[MstrCarpenter]

Sealed beam headlights in my '77 FJ40 Land Cruiser.

They don't put out anywhere near what my 2010 Tundra
does of course. But then, I don't drive it much at night.

Too bad the Tundra won't last near as long as the Land Cruiser. When a vehicle is engineered for recycling it is also engineered with planned obsolescence. I have a retro camper built on a 1989 E-250. Kids working the D.D. drive-thru think it's cool. It's about twice as old as they are. It also has sealed beams. They still get dimmer with age, but the mirror like coating on the inside falls off too. They're easy to change out so long as you don't drop the screws which is prone to happen, especially if you're working in a gravel parking lot.

[Snipe Hunter]

That's a lot of tape Neil!  I assume to avoid the overspray from a gun.  Would you have used that much with a rattle can?

So from Rock Auto I can buy TYO brand (NSF/CAPA Certified - if that matters) replacement lenses for $85 and $89.  (OEM are +/- $250 each).  Not much money, and it doesn't LOOK like it is that hard of a job...  I'd probably spend as much time putting that much tape on


Will I be disappointed with the quality if I do that?  Am I better off cleaning what I have?*  Would you put the 2K aerosol on new lenses (before installing)?

*Caveat:  Before I bought the vehicle, it was involved in a minor deer collision so one of the lights has been replaced.  It looks good now, but I figured I'd do both so they are identical matches over time.

There are others on Amazon for $132 for the pair, but a handful of complaints about moisture in them.  They say they are "DOT and SAE" certified.

Yes, the masking is for overspray. Even with a turbine HVLP gun, you'll get a foot or 2 of overspray. Maybe not noticeable to the eye but you'll feel it on the car. Masking is much easier than removing overspray. Also, I painted  a few  other areas on that car.

If you have a choice, always buy CAPA certified aftermarket parts. This is a rating blessed by auto insurance companies. They won't pay for non CAPA parts. CAPA parts fit and hold up well. Non capa parts are a crapshoot and quality is always suspect.

I have replaced lenses too but it it's cost prohibitive. Many cars these days need the bumper removed and some even need the fenders unbolted. Some need batteries removed and other internal parts removed and then there's the issue of adjusting. My labor rate is about $80 an hour. I charge $80 to fix two lenses which I can do in 45 min. I'd have to charge $300 to $400 to replace two with new parts. Closer to $800 for factory parts.