What breaks on Euro Headlights? Mystery glass inside...
 

Basically, the question is...

Besides the lens and the bulbs, what glass parts are make up a Bosch H4 headlight?

I bought a pair off fleabay and they arrived today. All the external plastic tabs appear intact, but as I handled them, I heard rattling sounds from inside. Some small grey plastic tabs shook out of the right side assembly. Tiny glass shards and a few more plastic parts shook out of the left. The lenses and bulbs appear completely intact, and they don't make any more noise now as I handle them.

I'm trying to figure out what broke. One of the glass chips has the typical lens ripple in it, but the lenses both appear excellent - no chips, cracks, voids, etc. It is as if the lens had been busted then replaced without cleaning everything out. The bottom lens clips is missing on the left side assembly which may also point to a replaced lens. What do the small grey internal plastic tabs hold?

Is it worth returning them? I paid $165 with shipping.

These are my first euro lights, so I've no clue what the inside is supposed to be like without disassembling these. I'm leery to do that if I expect to return them. I plan to contact the seller but first I'd like to have the necessary background info.

A previous bulb installed might have exploded. One of the late W126 assemblies I installed on my 300SD last summer had some pieces of an old bulb in it.

It sounds right that the original lens broke and was not cleaned up properly if the glass looks like lens material, with the ripples behind the glass (on one side) and smooth on the other side.

I would be more concerned that the reflectors are in good shape and that the housing is decent. Any tabs broken on the housing itself? Got photos for us to look at ?

Ditto what these guys said ... I took my Hella H4's apart this summer to fix up the reflectors, and I don't recall there being anything else glass in there. My guess would be the last owner had a broken lens or bulb and replaced it without noticing some glass bits maybe behind the reflectors. There are many little places for such bits to hide and pop out later. You may want to take the lens off and inspect to make sure all the flotsam is out.

The plastic tab might be off the plastic trim piece. If you take the glass off, thee is a plastic trim piece that goes around the outside edge --- it has tabs that "snap" into the light fixture.

I bet it's old bulb pieces too. You should take the lamps apart and clean them, just be very gentle when cleaning the reflector as it is easily damaged.

-Jason

+1

When the bulbs blow, they can fog the reflector and reduce performance. Be very careful if you wind up cleaning the reflectors. They are VERY easy to scratch.

The lens and reflector fogs over time too... hundreds of heat cycles cause dust to be sucked in.

When I cleaned the reflectors on my car I used a lens cleaning kit for camera lenses. It had a gentle alcohol solution and a very soft cloth. Even this put a couple small scratches into the reflectors. I used windex and normal paper towels on the glass.

-Jason