When I last replaced the battery in my W111, I was unable to fit the correct sized battery. In the end I fitted one smaller than I would have liked, but it was the only one that fit into the mounting frame I had. I knew the mounting frame was not original to the car as the previous owner purchased it on eBay. When he purchased the car, the battery was held down with ocky straps. At the recent German car day, one of the other members suggested my mounting frame might be from a W113 SL, rather than the correct W111 battery mounting frame.
On closer inspection I think he is right. the lower tray was clearly longer than the frame. In addition, the frame is not in good shape. There are sections where some of the metal has been cut away. This was probably to fit an incorrect battery. I therefore started looking for a replacement frame.
I was lucky enough to find one labelled to fit the W108, W109, W111 etc for bigger batteries. A new reproduction out of Germany and in the picture it looked great! Included with the rods to attach the W111 battery mounting frame to the tray (minus the wing nuts).
I tried the fit the frame last night, and it is huge. I can only assume that there was a special order option for a very large sized battery, or maybe from a W100 where everything is super sized. The photo below shows just how much longer the new frame is compared to the previous one.
This thing is gargantuan – hugely bigger than the tray it is supposed to fit onto. The comparison is even funnier when you lay the two frames on top of each other. The new one is about 50% larger than my current frame, which is only slightly too small.
I don’t have the specs for them, but I also need to try and research if the W111 battery mounting frame is a different size to the W108 or W109 unit, and if the one I have is for a W113. Nevertheless, it is clear that what I thought would be a simple part comes in a variety of different sizes.
My next step is to look at its construction more carefully, as perhaps about 10cm can be cut from it and it re-welded up. Since it’s a reproduction, i’m not ruining an original part. Otherwise back to the drawing board to find the correct frame. Perhaps my battery will have reached its 5 year life span by then.
I’m also looking to replace the battery in my ’67 250se Coupe and having a bit of trouble finding the right size. The Mercedes branded battery (A 002 541 99 01 26) I’m replacing has been discontinued and is now NLA. My battery frame is the same size as the tray and I assume it’s correct (sized to fit a battery roughly 11 7/8″ long by 6 3/4″ wide by 7 1/2″ tall).
Any ideas on what battery will fit? An american group 41 is 11 9/16x 6 7/8 x 6 7/8 and might work.
I have been told that a Yuasa battery fits very well. This is a brand that is available in Australia, not sure if it is available in the United States. Last time I got one I took my frame and the securing rods to the battery place for a test fitting. My frame is the wrong size, which made it harder for me. That is a problem you don’t have.