Yes I know, today the street price for new on these license plate light lenses is only ~$25 each which is one of the more reasonably priced MBZ parts... but there are two of them on these cars so that adds up to $50+ and my real pitch also is that IF you can perform this simple plastic repair, you might just find it easier to move up to more expensive lens repairs... say that $200+ tail light lens that's cracked and leaking !!
The first show-N-tell photo I have was taken after I had already repaired one other license plate lens on my Son's 1980 300D and when I checked the lenses on my own 1980 240D I found that both lenses were broken... so I had already started on what I knew would be easy repairs when I decided to write this up and propose it as a Do-It-Yourself Wikka... so here is my starting photo:
In addition to the broken lens, on the bottom lens note the white spot in the center that was caused from having too high a wattage bulb. These should NOT exceed 5 watts. And yes, you can see the typical type of break. Regarding the breaks we had, they were all on the longer " wing " of the lens. Yes, the " wings " where the mounting screw holes are located... one "wing" is longer than the other and so not surprising, the longer side breaks more easily.
While working on these lenses I also discovered the most likely cause of these breaks and wanted to put this discovery up front in this write-up. Take a look at the two following photos:
Photo #2 above shows the mounting hole under the lip of trunk lid just above the license plate. Note the " screw clips " that the mounting screws fasten through are still installed.
Photo #3 shows the other mounting hole with the " screw clips " removed to show how the holes are NOT symmetrical... and I found that although the lens will fit into the hole in either orientation, I believe that IF you put it in incorrectly, this most likely causes the lens to break in time... this and the fact that the paper thin gasket that originally went between the lens and the metal edges of the mounting hole, well I'm betting that these gaskets are long ago worn out. More later about gaskets and the special washers that cushioned the heads of the mounting screw. So remember that the longer attachment " wing " goes to the right where the slot is deeper!
Pushing ahead to describe how I affected my repairs of these broken-off " wings " let me first say that trying to merely glue them back together did not work for me, even when using a quality 2-part epoxy/resin as glue. The wing just broke off again... so I decided to put a form around the broken wind and build up a thicker layer of epoxy that I also reinforced to make stronger:
In photo #4 you can see I used cellophane tape to create a form to hold in the 2-part epoxy. You can also see the tape I put over the hole in the bottom of the lens fixture so that the epoxy would not leak out. At first I made my epoxy in small batches so I had multiple pours in what I felt was an experiment. This led to my inserting small washers inside my second epoxy pour as a way to reinforce my new built-up " wings "!
Photo #5 shows the new " wings " of my two lenses after they had hardened and I shaped them with my Dremmel Tool... NOTE the washers inside the epoxy.
I think this is a good time to reveal the type of epoxy I used on this project for thus far it has proven to be a good match for this DIY task. See Photo # 6 below. I used a product from my local Ace Hardware store... " ACE " item# " 18611 " which [as labeled] is a " Slow-Setting, " " Extra Strength " epoxy that dispenses the 2-part resin/ hardener from a double syringe-tube affair that is packaged in a neat way with a small mixing tray. The packaging facilitates storage of the unused portions of chemicals for use on your next project. I have had this for some time so I'm not certain what these sell for now or whether they are even available... let me see. Well when I look on their national Website, this product no longer shows up but I wouldn't be surprised you could find such a 2-part epoxy kit for under $10 at a local source in your area.
Pushing on Photo #7 shows a new gaskets I made using cork from a 6-inch square from another ACE product that I know is current... their Do-It-Yourself Gasket Kit, Item #4035499 which sold for about $3.50 which also has a rubber and hard paper gasket material as well.
Also in Photo #7 note two additional things:
(1) I crimped aluminum foil in the bottom of the bulb fixture to reflect more light out of this low wattage fixture [remember 5 Watts MAX]. Take care not to let this touch the conductors that the bulb is held in by, AND
(2) I epoxied a metal washer onto the outer surface of my built-up lens' " wing "... this so it would not get lost as can easily happen. Originally there were two washers under the fastener screws... a rubber washer to cushion and protect the plastic lens... and a thin metal washer to prevent the head of the fastener screw from griping the rubber washer. With my beefed up wings on my repaired lenses, I felt that I could retire those thin, worn-out, rubber washers and just go with a single glued-on metallic washer only!
So there you have it and I hope this helps to accomplish this small light lens repair. For me I figure this has already saved us ~$75-$100 and another $25 for each additional repair in the future... AND yes, I do feel more confident I can take on a repair of a much larger, more expensive lens in the future.
-" Samuel M. Ross " [ my handle on the FORUM ]
Discuss this DIY here.