W220 S Class ‘cloudy’ Headlamp lens replacement - RESULT!

[markben]

Some of you might remember me Posting recently about my original 18 year-old N/S Bi xenon headlamp lens / cover having gone terminally cloudy & yellowed. In daylight it looked ‘sad’ compared with the much newer crystal-clear O/S one. And.. although not an MOT issue (yet), the lens cloudiness was making the HID low beam light look fuzzy in darkness.

No amount of DIY or ‘professional’ polishing made a significant difference to its clarity and cosmetic ‘match’ with the newer one, and it gradually worsened. A complete new OE headlamp unit would cost upwards of £500 (Eek!) and of course even a ‘good’ used one would cost approx. £100 + fitting costs and still not match the clarity of the much newer headlamp . Even my local ‘pro’ bodyshop guy had shied-away from replacing just the lens. (Maybe too fiddly and / or not cost effective even for him?). Mmmm… I’ll say no more.

So: I took a gamble and ordered a sparkly / crystal clear new Acrylic lens from some nice Chinese folks via Eebuygum. £30 inc 7-day delivery. Hey ho, the quality looked good online, so worth a try? A few pals on another MB W220 forum in the US say they'd done the same with great results.

Today: with Heart in Mouth (in case of major problems), I fitted it successfully after doing some online research about the various technicalities. Rather than drag you through ALL 23 dismantling / re-assembly steps (!): only to say it’s a ‘fiddly’ job but not too complicated for a competent DIY-er and I completed it in just 2 hours.

The main (most common?) query about removing the acrylic lens cover is how, exactly, to detach it from the casing and soften the original VERY sticky airtight & weatherproof sealant. In my case: some gentle heat around the joint edge using a domestic hairdryer + some ‘easing’ with a sharp craft knife + plastic trim-removal tool worked ok. It takes patience, persistence & care: but the old lens was removed after about 10 mins - and leaving much of the original sealant intact in the groove between lens & casing without unsightly overspill on either. Phew…!

The delicate reflective silver coating & HID bulb covers inside the headlamp unit are pristine (still, after 18 years!). So I gave them a gentle brush-over & de-dust with a very soft artist’s paintbrush before attaching the new lens by pressing it HARD into the joint groove & remaining sealant and then re-attaching the sprung metal retaining clips after re-tensioning them for a tighter (& hopefully long-term airtight weatherproof) fit. Time will tell…

Result & Conclusion? YAY! So far, so good. An ‘As New’ looking N/S headlamp unit for less than 10% of the cost of a new OE one. Day & Night, it looks perfect. It’s only taken me 5 years to get around to it: but worth the wait, time & effort!

Here are the Before & After Pics, hope this helps anyone here who’s considering doing a similar project? I'll be pleased to answer any questions from my (stress) 'Amateur' experience of doing this DIY Headlamp Restoration Job.

MB

‘The Best or Nothing’

 

[DSK]

Thank you for the update and what a result! Looks just like an S Class should. You were right to try the lens option first.


Sent from my iPhone using Tapatalk

 

[markben]

Thank you for the update and what a result! Looks just like an S Class should. You were right to try the lens option first.


Sent from my iPhone using Tapatalk

Yep and thanks DSK! I'd niggled about and dithered around about how to fix the cloudy headlamp issue for ages. But today all came good - and it reminded me that fixing these types of things isn't necessarily as complicated or costly as feared!

 

[mioba]

Well done OP. Looks great.
Did you spray on some UV proof lacquer.

Now we need the 23 steps plus pics.

 

[markben]

Well done OP. Looks great.
Did you spray on some UV proof lacquer.

Now we need the 23 steps plus pics.

Thanks! No I haven't applied any lacquer (yet..). The other headlamp is about 8 years old and not showing any signs of yellowing / cloudiness, maybe because I clean the car thoroughly every week?

Sorry I didn't stop to take photos of the job stage by stage because I was impatient to get it finished! And I didn't post all 23 steps here bcs I thought it would end up as a 10 page Novel! . But there are some yootob video tutorials on this topic if you search for them?

One issue to be aware of is how to seal the new lens to the casing effectively. Someone here has suggested heat activated automotive adhesive to make it airtight & weatherproof whilst being able to tolerate extremes of heat & cold - I can't argue with that. But I've also seen a video tutorial by 'Mercedessource' (Kent Bergsma) in the US who just recommends clear silicon + nicely tightened retaining clips. Dunno which is best...?

I think the other main tip I would share is that you don't need to remove the bumper (valance) to remove the headlamp. Just remove the 2 downward facing retaining bolts (inboard of the headlamps) and gently ease / prop the bumper outwards by about an inch or so. This way you create just enough clearance to slide the headlamp out / back in.

That said, if anyone here has any specific questions about this fix, just ping them to me and I'll try to help.

 

[alexanderfoti]

I did this with my 221, although the lense was close to £120 each from the same kind chinese suppliers.

 

[horatio]

Cheers for posting the result, they look super!

I’ve taken headlights like these apart a few times and I like the original butyl putty stuff. It seals well, it’s reusable and you can take the lights apart again if need be with the chore of picking old silicone off.

You could ceramic coat them.

 

[alexanderfoti]

Shoving them in the oven at 50C for 10 minutes makes the sealant very soft and pliable, with no damage to the headlights.