| 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 […] 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 […] My 1986 300SE is now back in business with good oil pressure. Turns out the reason why the oil pressure was low was a catastrophic failure of the oil pump itself. In the last part, I had narrowed the problem down to most likely being the pump. I assumed that something was either blocking the screen or the pressure relief valve was stuck. At this point it was time to take the car to a professional mechanic to have a look. On the M103, the engine has to be raised to remove the one piece sump. Once the sump […] As a recap, my 1986 300SE started showing low oil pressure. I tried changing the oil and filter, replaced the sender and checked with a mechanical gauge. Still low oil pressure. I decided to do some final oil pressure troubleshooting before I took it into a mechanic to lift the engine and remove the sump. I was advised on the ozBenz forum that another possible cause was the oiler tube for the camshaft coming loose. The oiler tube is held down by a couple of bolts that if overtightened can strip the threads. Since I don’t have a lot of […] In my last update, I had ruled out the sender unit when it came to the low oil pressure readings on my 300SE. My intention had been to take the car to a mechanic to test it on a mechanical oil pressure gauge. Two things changed that. Firstly, my area of Sydney went into lock down. Secondly, most mechanics are on holidays until after the new year. I therefore purchased my own mechanical oil pressure gauge off eBay. I hooked up the gauge and sadly the results were much the same as the dashboard gauge. The mechanical oil pressure gauge […] 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 […] Today I took my 300SE on a Mercedes Club Pop up drive. The Pop up drives are short notice mid-week drives. I normally take the other cars to club events, but the 300SE had not been on a decent run for a while and the weather was terrible. The drive was down through the Royal National park to Mt Kembla, Mt Kiera and then back. The other cars on the drive were rather varied. There was a Ferrari 458 Spider, an Audi SUV, a race prepped Toyota Yaris and a couple of other Mercedes including a C63, C250 and E400 […] A week or so ago, I diagnosed that the likely cause of my non functional A/C in the 300SE was the W126 Klima relay. The second generation W126 went to a Klima relay to control the A/C compressor. The W126 Klima relay is more of a control unit than a simple relay. It has multiple inputs that determine if the A/C compressor should not engage. These include: During full throttle When the engine is very hot Invalid compressor speed (e.g slipping belt) Not enough coolant in the system This additional functionality makes these relays more sensitive than the little silver […] There is an old saying that deaths come in threes. I’ve not had any deaths in the family, but I had the A/C dead in three cars at the same time. The easiest was the A/C in my 450SLC that just needed a re-gas. The W126 A/C has been more problematic. Just as I got the system in my 560SEC mostly finished, the A/C stopped working on my 300SE. I took the car in for the gas pressures to be checked and the gas was not below minimum spec. A tiny bit was added but my mechanic told me he […] Today I changed the Distributor cap and rotor in my 1986 300SE. I bought the new cap and rotor about two years ago but only just got around to changing it. Unlike on the earlier engines, the M103 distributor cap is a fiddly job. Instead of sticking upwards, it comes out sideways as it attaches to the camshaft. I find that whenever I buy one of these older cars, chances are the distributor cap needs changing. It is not generally an expensive part on the mainstream engines, and can make a big difference to the smooth and reliable running of […] | |
