Guest Post: W126 parking brake shoes

I purchased my 1989 420SEL about two years ago and have been busy doing a lot of work to the car to bring it up to my standard. My most recent job was to inspect and replace the W126 parking brake shoes. The parking brake was not holding the car, even after I adjusted it. The Mercedes W126 uses a separate set of drum brake shoes that act on the inside of the brake disc for the parking brake.

Last weekend I started the job, and at first it was pretty easy. The wheel and caliper was off in no […]

560SEC outside temperature display

Last week I fixed the outside temperature LCD on my 300SE. Today it was time to fix the 560SEC outside temperature display as well. In my previous post I covered the details of where I purchased the replacement LCD panels. This same repair should also work on W124 and W201 models of the same vintage. I understand there are minor variances, and that the LCD changed slightly in later years. Both types are available.

I found a few things to speed up the process while doing the second car. Firstly, the instrument cluster does not need to be unplugged. It […]

W126 Outside temperature LCD screen repair

For the first time since I have owned the car, my 300SE has a working outside temperature display. Not only is it a useful feature of the car, but these small fixes can make the difference between the car seeming nice or a bit of a jalopy.

The W126 Outside temperature LCD repair is really easy. It should be on the radar of any W126 (or W124) owner who has a failing outside temperature display. It only took 30 minutes and is very easy. Even better, the LCD illumination works when the headlights are on, when I thought it was […]

W126 Outside temperature LCD screen repair attempt 1

The W126 outside temperature display was standard in all Australian delivered series 2 models. The little LCD screen is not really compatible with the Australian sun as most of them start to bleed and become unreadable. My 300SE and 560SEC both have unreadable LCD screens. The 560SEL, which was garaged all its life still has a good screen.

Buying a used one is not really a good option. They are not particularly cheap, and even if a cheaper one from the USA can be sourced, it would be in Fahrenheit. There is somebody in Europe who is selling replacement LCD […]

W126 Radio and USB sockets

When I bought my 300SE about four years ago, it came with an early 2000s era Kenwood CD player. At the time, I assumed I would need to replace it, as it wasn’t working. Turned out the plug had come out of the back and it actually worked fine. It wasn’t a bad unit, as it could play MP3 CDs, display track information and so on. My main problem with this radio was that it would occasionally cut out, and only work again if I removed and plugged the face back in. The W126 radio is a DIN unit, so […]

W126 battery hold downs and Auxiliary fan resistor

When I restored the battery tray on my 560SEL, I noticed the W126 battery hold downs were missing. While the battery on the W126 sits quite snugly between the inner and outer firewalls, the hold downs are still important. On a serious bump the battery could short out against the bonnet for example.

These hold downs are the same as on the W123 and other models. I ordered a new one, thinking that at least having one in place would start, and I would look for a cheaper used one later. Turns out I needn’t’ have bothered as I found […]

M103 Oil pressure sender

A few weeks ago my 300SE started to show low oil pressure on the gauge. It happened all of a sudden while on a drive. At the time, I surmised that I had a dead M103 Oil pressure sender. They are apparently a common fault. I ordered a new one and fitted it today.

The M103 oil pressure sender can be found on the side of the oil filter housing at the back of the engine. Most of the threads you’ll find on the various forums are referred to the W124. Apparently on the W124 space is tight and it […]

December 2020 W126 Price Guide – Australia

When I wrote my W126 buyers guide earlier in the year, I did not include price information. Pricing is very specific to each location and changes frequently. This W126 price guide covers my observations about the prices of W126s in Australia. Its likely to be valid for the next year or so.

There are a few factors that impact the price of a W126. Some models, years and options are worth more than others. This is particularly the case for the W126 which had different body styles, engines and even two distinct series. As an example, the V8 models are […]

W126 power rear seat top trim

An obvious issue on my 560SEL was how the rear seat was mounted. There was an obvious gap between the parcel shelf and the rear seat. The 560SEL came standard with a W126 power rear seat. This either standard or optional on other W126 LWB models. It seemed clear that when the self-leveling rear suspension was removed, the trim was not put back correctly.

On a car without the power rear seat, the backrest is fixed into position so there is no need for an additional trim piece. On a car with the W126 power rear seat, there is a […]

W126 Monovalve eliminator – part 4

I have now completed the installation of the Movovalve elimination kit on my 560SEC. So far so good. Most importantly, I don’t have heat when I don’t want it, but it is available when needed. In the last installment, I completed the routing of the cooling hoses. From there I installed the radiator and ensured the cooling system didn’t have any leaks. The final step was to set up the vacuum solenoid so it could control the heater valve.

The very rough diagram below outlines how I adapted the kit for the W126. Note the diagram is not to scale […]