Are your headlight lenses getting cloudy?

They are plastic with an optical coating.

After years, the wind with it's little grains of sand 'sandblast' the
optical coating and the lenses start to fade and turn yellow.

There isn't really much to do except install new headlights.

 

Like any finish lens cover require preventive maintenance . If cleaned and
protect by a polymer polish on occasion and they will not cloud over.


mike hunt

 

Sorry to disagree but my Aerostar(86) had plastic lenses as well as the
whole bulb until I replaced them with glass ones

 

There are two other options (see (1) and (2) below). The cloudiness is
a surface issue - not thru-the-material.

For (1) or (2), it would be best to remove the assys. from the vehicle.

(1) You can sand the surface with ever finer grades of wet-or-dry,
ending with 2000 grit, and then polish with any one of a number of
polishes - Mequiar's Plastix™ being one that works well. But you do
have to periodically repeat the polishing. (Note: When the sanding is
finished, the surface will look uniformly dull - never fear - the polish
fills in the microscopic sanding scratches to make it look brand new.
While not necessary, if you polish it long enough, you will smooth it
down to a water clear surface, but polish will still be needed
periodically to protect it from deteriorating again without the clear
coat that originally came on it.)

- or -

(2) Sand it down as in (1) above, and then (after insuring that no
chemical residues remain from sanding and/or polishing) clear coat the
surface with regular clear coat - many people have found this a very
satisfactory solution. Just like the polish in (1) fills in the dull
finish (after sanding) to make it appear water clear again, so will the
clear coat.

Also, whether replacing with new assys. or clear-coating, these might be
a worthwhile investment:
http://www.autosportcatalog.com/index.cfm?fa=p&pid=332
Worst-case, you might have to replace one set of those over the
remaining life of the vehicle - much cheaper than new headlamp assys.

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
address with the letter 'x')

 

Hi Bill...

Just to add to your sanding process for what it's worth...

Autoglass people have a product they use... a pink liquid, used
to polish windshields, that easily polishes plastic to a brand
new gleam.

Wish I remembered (if I ever knew) what it's called. How I came
across it was years and years ago one of the kids went up north
in a 79 pontiac wagon. Coming back it rained, the passenger
wiper somehow ripped, and time they got back there was an awful
gouge in the glass... neighbor was then in the autoglass
business, and gave me a coke bottles worth of this stuff.

BTW, lots of elbow grease removed every last trace of the gouge,
but by the time it was gone the glass was optically changed.
In this case didn't matter, lower strip on passenger side,
but if any others try it be careful

Take care.

Ken

 

Yeah - anytime you remove material (change the thickness) unevenly, it's
going to cause optical distortion. One of my kid's car's windshields
has an arc from the windshield wiper arm from one night several years
ago in which the wiper blade fell off in the middle of a bad storm and
they kept driving with the wipers running with it like that - it's not
too noticeable, and not deep - just surface abbrassion - I'm hopting
that if I ever get it polished out, it won't cause noticeable distortion.

I've concluded that some glass is *much* harder than other glass. I
worked on it by hand with tooth paste and some other abbrassives - even
tried wet-or-dry on it. Didn't phase it. I even got my Dremel
MotoTtool out with the polishing wheel and abbrassive - still didn't
have any effect! There's a shop in town that's supposed to be set up
for removing windshield scratches - as soon as I get it back on the road
(replacing head gasket now) I'm thinking of taking it by there and
paying to have them see what they can do. Another shop in town says
they don't do that any more - they just insist on replacing the
windshield - which I guess is more proftiable for them, and in some ways
makes sense for the customer too. I just prefer not to break the
factory seal if I don't have too (plus I have learned that factory
windshields are made of much harder glass than typical consumer grade
windshields - and therefore much more resistant to sandblasting and
other damage (and polishing out of scratches once they do occur).

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
address with the letter 'x')

 

Yep. Glass comes in all kinds of different hardnesses. And then there's
hardened glass, and toughened glass, and...

Cerium Oxide slurry is the appropriate gookum.

That's why you want to insist on reputable-name-brand glass when having a
windshield replaced.

DS

 

If it's pink, the active ingredient is probably cerium oxide. It is used in
optical work quite a bit, as it cuts and polishes faster than rouge. It's
also less messy. Personally, I would make a lap with optical pitch to do the
polishing, and avoid the sanding altogether.

Steve R.