Wet Sanding Headlights - Mercedes Sprinter

[Wingz123]

You will need...

1x sheet of 1500 grit wet and dry

1x sheet of 2000 grit wet and dry

Cutting compound - g3 or g7 or similar

Rotary polisher (not essential but better results achieved quicker using a rotary polisher)

 

As is mostly the case on older cars, the headlights (as a result of UV Ray's from the sun) fade and yellow the headlights which can massively reduce the light output. This was something my Audi A6 was suffering from and had been for some time after trying many other 'remedies' which would work, albeit temporarily and after several days in some cases would be back to how they were before I started. I tried an array of polishes and even a suggested toothpaste!! Which yes may improve but this is not permanent. 

Anyway, after investing in blue automotive tape, wet and dry paper in two different grades I was primed and ready to have a go at wet sanding the headlights. Had always been a bit dubious in case I screw up or damage the light!

Here is how the lights look to begin with....

Anyway, with the areas taped up I began with 1500 grit wet and dry in a bucket of water.

I began rubbing the headlight where it  began crying tears of white although was noticeably smoother after even 5 mins of rubbing! However, I didnt just want a slight improvement, I wanted these to be how they were or as close to when brand new. After a good while (I was in no rush), I switched to 2000 grit and continued again for a fair amount of time. Essentially I would go until no white residue was any longer produced when rubbing the light. 

 

It was by this time feeling ultra smooth and you can already see the distinct reduction in yellow-ing! The final step was to use my newly acquired rotary polisher with some cutting compound on to finish off the lights and get rid of any fine scratches (I raided my valeting cupboard but truth be told all I could find was some T-Cut so this is what was used!) Farecla G3 would have been better ✊?

And after all that here are the results....next up my Sprinter!

2x coats of Collinite 476s was then applied to the entire car and 5x Collinite 476s coats of wax was applied to the headlights however you could go one step further with the headlights and lacquer them but I didnt have any lacquer and I'm now sure they shouldn't go back to how they were anytime soon....am running 8000k HIDs (yes come and arrest me) and the light output has improved no end as I'm sure you've guessed!

 

[Iamgroot]

Good work!, I remember having to do my old Laguna headlights to get it through an MOT, before it was a common thing and information was around, me and the Mrs using nail buffers on them while sitting watching TV over three horrible nights.

Worked but didn't look as pretty as yours do now.

[Fumbler]

This is useful stuff. Will recommend to Father so he can restore his MR2 lights.

[DoctorRetro]

Does this method work for plastic lenses? 

[Wingz123]

5 minutes ago, TheDoctor said:

Does this method work for plastic lenses? 

Yes these are plastic lenses - if you lived close enough I'd say bring it over and I'd give you a hand

I have a day off tomorrow so will try and make a start on my Sprinter. Those lights are very bad so will be interesting to see how they come up! Pictures will of course be taken and shared!

[bunglebus]

I have to give my Passat ones a good T-cut/G3 about every 6 months, still can't get out some marks that I think are from that nasty stuff hand car washes apply with a garden sprayer. Haven't been brave enough to use sandpaper yet.

[FakeConcern]

Excellent result on the Audi! I did both my daughters Clios plus Mrs Concern's Modus. The problem is it doesn't last and I would buff them up each year with polish and a DA before the MOT

[bunglebus]

Does lacquer work? 

[stonedagain]

Just now, bunglebus said:

Does lacquer work? 

No, you need to use a  UV resistant coating.

[Bren]

3 minutes ago, bunglebus said:

Does lacquer work? 

Without the lacquer you will be doing it again in a few months.

[Bren]

The lacquer is used is for headlights - not clearcoat.

[Lord Sterling]

I don't have the sandpaper needed for the job but a mate started with some cheap cutting compound.

1st attempt by hand made some difference:

2nd attempt looked a lot better:

I tried later with my rotary polisher and some proper T-cut but it made little difference. It's better than what it was though.

[richardmorris]

Nearly all the Citroen c6s ( and there were a lot) at last weekend’s chevrons Rally had cloudy plastic headlamps. My 2002 c5 had one awful lamp and one perfect. I don’t know why.

[Wingz123]

2 minutes ago, richardmorris said:

Nearly all the Citroen c6s ( and there were a lot) at last weekend’s chevrons Rally had cloudy plastic headlamps. My 2002 c5 had one awful lamp and one perfect. I don’t know why.

Probably replaced at some point in its life for a new remanufactured unit that you can buy from carparts4less or the like. My friends Golf is the same......Before I told him I was wet sanding he said "have you tried toothpaste?".....I said let me stop you right there.....

I applied 5x coats of wax to try and protect against the UV rays/water. There was no reason I applied 5 it was just the way I waxed the car a panel at a time that when I did the wing individually and the bonnet Individually, being so close to the headlight I would get a bit on the headlight so ended up giving it another full coating hence there being 5 coats in the end....

Cant wait to do my Sprinter.....we'll see how they turn out although the reflector bit inside isn't in the first flush of life!

[richardmorris]

5 minutes ago, Wingz123 said:

Probably replaced at some point in its life for a new remanufactured unit that you can buy from carparts4less or the like. My friends Golf is the same......Before I told him I was wet sanding he said "have you tried toothpaste?".....I said let me stop you right there.....

I applied 5x coats of wax to try and protect against the UV rays/water. There was no reason I applied 5 it was just the way I waxed the car a panel at a time that when I did the wing individually and the bonnet Individually, being so close to the headlight I would get a bit on the headlight so ended up giving it another full coating hence there being 5 coats in the end....

Cant wait to do my Sprinter.....we'll see how they turn out although the reflector bit inside isn't in the first flush of life!

Possibly, but it was four years old when I bought it. 

[Wingz123]

Odd you never know though could even have been something as silly as where he parked his car at home and only half of it being in the sunlight all the time or whatever. 

I really recommend doing it this way. Is much more long term than a polish as other have said, polishing them is only temporary and you'll find yourself having to them again. 

My neighbour came out and asked me what I was doing. He was absolutely fascinated because he had seen for the many months previous just how bad they were. 

Oh and definitely easier doing them in situ as opposed to removing the headlight units and trying to do them on the bench for instance or on your lap in front of the telly. 

[Luxxo Waftybarger]

Without UV protective coat applied afterward it's a waste of time. Give it 2-3 months and they'll be the same. They go bad in the first place because the factory UV protection breaks down.

[Wingz123]

1 minute ago, Luxxo Waftybarger said:

Without UV protective coat applied afterward it's a waste of time. Give it 2-3 months and they'll be the same. They go bad in the first place because the factory UV protection breaks down.

What would you suggest - can you suggest a brand/make and I'll get it and apply ?

[Luxxo Waftybarger]

I've used rattle can stuff but it makes a mess. 3M do wipes I'd be tempted to try them. The cloudy plastic is oxidised, by sanding you remove the oxidised plastic exposing fresh slightly less unoxidised plastic. It will eventually also oxidise too but the clear coat delays that. Just don't want you to think it will last forever!

[FakeConcern]

27 minutes ago, richardmorris said:

Nearly all the Citroen c6s ( and there were a lot) at last weekend’s chevrons Rally had cloudy plastic headlamps. My 2002 c5 had one awful lamp and one perfect. I don’t know why.

That's interesting, I've had three C4 VTSs and none of them suffered from this and I've never seen one with cloudy lamps either. You'd think with them being from the same era both would be made with the same process.

[richardmorris]

7 minutes ago, FakeConcern said:That's interesting, I've had three C4 VTSs and none of them suffered from this and I've never seen one with cloudy lamps either. You'd think with them being from the same era both would be made with the same process.

My suspicion is that Citroen specified / bought cheap plastic. *

 

* the fiat tank steel de nos jours.

 

edit. This sort of quality product finish is why I drive a 25 year old Mercedes ( with glass headlamps) as my daily car. 

[Luxxo Waftybarger]

Sometimes it's too far gone. Eventually gave in and bought new lamps for my 2005 Micra, after 3 consecutive years of MOT fails on cloudy light I'd had enough.

[Wingz123]

Here are the wipes you mention...

https://www.amazon.co.uk/3M-39173-Quick-Headlight-Clear/dp/B079QL8BYK

I'd thought a good quality wax would do the same. This Collinite 476s is decent stuff and well regarded not the cheapest stuff either.

[richardmorris]

10 minutes ago, Luxxo Waftybarger said:

Sometimes it's too far gone. Eventually gave in and bought new lamps for my 2005 Micra, after 3 consecutive years of MOT fails on cloudy light I'd had enough.

Citroën C5 hdi headlamps cost more than the car is worth! 

[Wingz123]

12 hours ago, Lord Sterling said:

I don't have the sandpaper needed for the job but a mate started with some cheap cutting compound.

1st attempt by hand made some difference:

2nd attempt looked a lot better:

I tried later with my rotary polisher and skme proper T-cut but it made little difference. Its better than what it was.

These Vectra headlights are another favourite for the old headlight fade. When I was out in Spain earlier this year practically everything had it......obviously....

[Kiltox]

Top results - I reckon this age of Audi is about the worst around for clouding headlights. 

[barefoot]

The woman up the road has a Daewoo Matiz. It failed its MOT on headlights and the bloke at the garage gave her some T cut which she (and I) spent ages pissing about with & it staggered through its MOT. Some months later she broke her windscreen & the AutoWindscreens bloke apparently told her to do her headlights again with a paste made of mixture of baking powder & water. She tells me that she gave it a try and it took her no time at all.

This may of course, be complete bollocks.

[Wingz123]

Thank you all for your comments. I am planning on starting the Sprinter this afternoon. Have taken today and tomorrow off as holiday then am off to the Isle of Wight with the car on Saturday morning. 

These pictures dont actually tell the full story.....they are a lot worse in real life! 

[overrun]

3M kit and a tin of lacquer makes the most sense for doing this, IME.

[Lord Sterling]

On 9/26/2019 at 9:35 AM, Wingz123 said:

These Vectra headlights are another favourite for the old headlight fade. When I was out in Spain earlier this year practically everything had it......obviously....

The Vectra actually had a layer on cloudiness on it with a slight brown tint. My mate with the Blue Vectra managed to rub a bit off with a bit of water and his finger. It might just have been decade old lacquer or something. The inside of the light might need some cleaning. But its a lot better now than what it was. Practically everyone was commenting how the lenses looked dull.