Hi everyone. I have a 2009 XK and the headlamp projector lenses are somewhat milky / cloudy. I have seen pictures of other owner's XKs which show very clear projector lenses, but those have been newer model years than mine.

So - my question is this: should my projector lenses be crystal clear? Or is this just how they came from the factory in '09? If you have an '09 (4.2) or earlier are your lenses crystal clear?

As a side note, I am pretty unimpressed with the headlight illumination compared to my newer Mercs - which have outstanding illumination ("night and day" so to speak). I am replacing the HIDs this weekend as a start - but I am wondering if the issue goes deeper.

I have taken a couple images below. They don't pick up the cloudiness well, but hopefully they will be useful for comparison.

Thank you in advance for your collective wisdom.


Ignore the horizontal lines. This was a strobe effect from the LED flashlight I was shining through from the back.

Ignore the horizontal lines. This was a strobe effect from the LED flashlight I was shining through from the back.

 

It should be cristal clear
I had such milky on one side, opened the front lens and cleaned the projector lens. Now it's cristal clear

 

Thanks Danny. Was the milky coating on the front or the rear of the projector lens? And did it require polishing, or did it just wipe off?

To get at the front of the lens, I'll have to pull the housing apart. Other members have provided good direction on how to do that.

To get at the rear of the lens, it looks like I *might* be able to remove the high-beam flap from the bulb opening to provide access to the lens (the flap housing appears to be held on by 4 torx screws) - but I am not sure. I'll cross that bridge if needed.

Many thanks!

 

It's on the back side just in front of the bulb
It went off with some alcohol but I couldn't do that through the bulb service opening

 

OK - so to get at the rear of the projector lens you did the full housing disassembly (using the oven baking technique) I presume?

Thanks again Danny - this is very helpful.

 

No baking...few screw drivers, knife and a lot of patience

 

Got it - thanks so much!

 

Yes bake it to remove lens - much easier than hacking away with knife/screwdriver etc.

 

Thank you Hafren. I found that thread (and appreciate you attaching the download).

Looks like I have a weekend project now!

 

Thank you Hafren. This will come in handy someday

What is your opinion on using adhesive to seal. I am guessing its the same as the kind used on the windshield?

 

If it’s on the backside of the projector lens between bulb and lens, couldn’t you just remove the bulb and clean lens from there? I haven’t removed bulb so don’t kill me if that’s a dumb question...

 

It’s black butyl readily available on many sites including amazon

 

QC, When you remove the lens the adhesive stays in place so you can assemble back asis. It is much more difficult to remove the old adhesive than reuse it...

 

Thank you!
Here is one back at you.
I have boat loads of this stuff, we use it to mount sub drivers.

 

Danny you are teaching people how to steal our lenses, they just have to wait for summer.
Dont be surprised they steal cat converters and side view mirrors.
https://www.thedrive.com/news/27876/...on-modern-cars

 

I'm not sure if i need to be laughing or worried now

 

Access to the back of the lens via the bulb opening is super tight. There is the high-beam flap partly in the way, plus the lens is deep inside a housing.

I looked inside mine from the back, and I am not convinced the milkiness is a film on the inside of the lens as it was in Danny's case. In my case, the backside of the lens seems to be clean - as best as I can tell while it is still assembled.

I'll be firing up the oven this weekend to take one apart, and will let you all know what I find when I get better access to the projector lens.

Thanks again for all the great advice / pointers / experience.

 

OK - so I took the headlamp units apart today. The projector lenses had a coating on them - both sides. It was a white, milky coating that came off easily with the wipe of a soft cloth. To get at the lenses, the internal housing for the lenses had to come apart and be removed. It was easy - four additional torx screws and some careful prying of tabs that held the lenses in. I have a feeling clean lenses is going to make a big difference to the headlight beams. They were somewhat weak and diffuse before. Once I get them back together I'll see how big the difference is.

I used the oven technique and it worked like a charm. In addition to the excellent guide on this forum, I checked other resources because I was worried about the heat. Interestingly, those other resources suggested temperatures from 200 - 220 - so the 160 in our forum's guide is conservative. But it was enough to do the trick - plus less risk, of course. Additionally, what I did is I heated up the over then turned off the oven before putting in the headlamps. I did not want to risk a hot element creating too much heat near it. Our oven holds heat for a long time, so this worked perfectly. I was also easily able to handle the headlamps without gloves - which is a bonus.

I can't put them back together just yet because I discovered that the wire insulation in one of the lights had become brittle and failed in many places (no - not as a result of the oven - I saw it before taking them apart). So tomorrow's task is cleaning all that up. I'll post that update in another thread.

In the meantime, see below for a before and after of the lenses. The difference in person was more striking than it appears in the photos.