About the 300SE
The 300SE is an S-Class of the W126 range (1980-1991), a car that many enthusiasts regard as the last of the classic ‘over engineered’ Mercedes. Being a 1986 model, it is the first year of the updated Series 2 model, which featured improved engines. It does not have the interior upgrade, as that did not happen until 1988. The 300SE was the entry level S class in most markets (including Australia), with the 260SE mostly focused on markets with punitive taxes for engines over 2.8l. For more information about the W126 in Australia, see this post.
The 300SE is a bit of a hidden gem in the W126 range. Livelier and better to drive than the 420SEL, but half the cost.
About this car
I owned this car from January 2017 to January 2023. I bought it to be my everyday driver. The 450SLC has in some ways filled this role since I purchased it in 2003, but for nearly all of that time I used public transport for commuting (or had an underground parking garage). Circumstances changed and I needed a car that could fit 3 child seats across the back. W126’s are still very reasonably priced and fit these requirements.
This 300SE is an entry level model, without many options. This is perfect for my needs for driving the kids around. Upholstery is MB-TEX, and there is no sunroof orpower seats to go wrong. It does have automatic climate control, but this is how they were all ordered by Mercedes Australia unfortunately. And being a 1986 it can be registered as a classic car, which I would do about four years into my ownership.
The car was purchased from the next suburb to mine and came out of long term ownership. The Signal red paintwork is a nice change from the mostly champagne or white W126’s that are seen around. I have since removed the chrome wheel arch trims that were installed on the car at purchase. I put about 16,000km on the car over my six years of ownership.
Option codes
| Option Code | Meaning |
|---|---|
| 233 | Foglamp wiring for F/CH/AUS/S/N |
| 240 | Outside temperature indicator |
| 259 | Becker Radio Grand Prix Cassette Stereo Electronic |
| 286 | Luggage nets on front seat backrests |
| 420 | Automatic Transmission (Floor Shift) |
| 430 | Headrests in the rear |
| 440 | Tempomat (Cruise Control) |
| 470 | Anti-Lock Brake System (ABS) |
| 480 | Self Leveling Suspension |
| 507 | Outside rear view mirror left and right heated (Electric adjustment Left) |
| 531 | Automatic Antenna |
| 543 | Sun Visors with vanity mirrors, illuminated |
| 551 | Anti-Theft / Break in warning system |
| 574 | 570: Folding arm rest 571: Front seat left, with height adjustment RHD |
| 588 | 581: Automatic climate control 584: Electric window lifters, front and rear |
| 599 | Heat Insulated glass, side and rear window panes, windshield clear |
| 615 | 611: Courtesy lamps, front and rear doors 613: Lamp unit, Asymmetrical, LH Traffic |
| 625 | Version for Australia |
| 677 | Tropical battery |
| 731 | Wood trim, burred walnut root |
| 806 | Model year 1986 |
| 812 | Rear-mounted loudspeakers |
| 877 | Reading lamp in the rear |
Related posts
Today I purchased a 1986 300SE W126. I needed a car that had room for three child seats when necessary and was eligible for historic rego. It also couldn't cost too much money. Enter ...
The 300SE didn't come with much concrete service history. I started a full service on the car to establish a baseline. This will allow the car to be properly maintained to the factory ...
My ownership of the 300SE had been off to a good start until 3 issues reared their ugly head in the last couple of days. As outlined in the last post, the first issue was ...
My 'new' 300SE suffered from a common problem with Mercedes of that era, a non functional odometer. The mechanical odometer is driven by a small electric motor instead of a traditional speedometer cable and ...
When I purchased my 300SE, the A/C worked well. I assume the overall Climate Control system did too. I never did test anything more than max A/C as the weather was very hot. Everything ...
When new, a W126 Mercedes would have come with four keys: Two square headed master keys. One round headed valet keys. A flat 'wallet' key. The master keys were designed for everyday use and opened ...
The 300SE had a severe stumble at idle. It only occurred when the engine was hot. It never stalled the engine, but felt like it was about to. There was also a miss ...
Previously, I had identified that the cause of my A/C problems was the fuse blowing. I have been narrowing down the problem more and more to the compressor clutch. Therefore, I wanted ...
Recently on the 300SE I had to make a decision if I would fix the head gasket or junk the car. To do the repair right was going to cost pretty much what I ...
The 300SE has been suffering from poor hot starts. It required a lot of cranking before it fired. On a K-Jet car, this is normally caused by a faulty fuel accumulator. From what I understand ...
I've been fighting with the W126 Climate Control system for the last few months - and it's been winning. When I purchased the car in November last year, it was a very hot day ...
My story of fixing the W126 climate control can be summed up by: If everything points to a problem with an expensive part, don't waste your time trying to replace the cheaper parts around it ...
My fight with the W126 Air Conditioning system is almost over. When I purchased the car, the A/C worked rather well. After the water pump gave out, it looks like it shorted out the compressor ...
The saga of my non functional A/C is now over. The 300SE is blowing cold air. It would want to after all the parts I had to change to get this far. The final piece ...
The motor mounts were changed on the 300SE around six months ago, but there was not time to do the Transmission mount. It was obvious it would need doing from the condition of the motor ...
Back in early 2017 I fixed my broken odometer. The 300SE odometer repair was successful, but there were two things I needed to follow up on. The odometer was reading 10% low. I could hear ...
At least in Australia, by far the best month of the year to buy tyres is June. Both the tyre retailers and manufacturers offer attractive end of financial year sales. Most people don't realize, ...
A few months ago I replaced the under bonnet insulation pad on my 560SEC. This job also needed doing on the 300SE. I purchased both pads at the same time, and finally got a chance ...
A common feature of Mercedes cars from the mid 70s through the mid 2000s is the self-leveling rear suspension. This system is standard on the wagons, but was commonly specified on the higher end sedans ...
Today I did an engine and transmission oil change on the 300SE. I don't normally post basic maintenance to this website as it really isn't that interesting. In this case, I used to tips I ...
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 ...
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 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 ...
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 ...
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 ...
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 ...
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 ...
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, ...
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. ...
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 ...
Last year, while I was fitting the monovalve elimination kit to my 560SEC, I cleaned the drains under the cowl covers. I also fitted a new upper seal and new shaft seals for the ...
Another long standing to-do list item on my 300SE was the passengers side window. Over time, the window would slip down so there was half a centimeter gap at the top. It would also make ...
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 ...
Back a few weeks ago I identified the problems with my power window was the W126 front window regulator. In particular, the passengers side front. The regulator was missing some teeth. I had bought a ...
On a recent drive with a few friends I noticed my 560SEC was sitting a bit low at the rear. I had it parked next to a 380SEC, which I am pretty confident is at ...
When inspecting the SLS in my 300SE, I noticed that the fuel pump was seeping fuel. It wasn't enough to smell fuel, so I am not sure how long it had been like that. ...
I've been meaning to change the brake hoses on the 300SE for a while. I have no history for the car, so I don't know how old they are. As I also wanted to change ...
I recently changed the flexible brake hoses in my 1986 300SE. I wasn't sure how old they were and they are a wear item. The next step was obviously bleeding the brakes. Bleeding W126 brakes ...
For Sale: Australian delivered W126 300SE in striking signal red and cream MB-Tex interior. Both interior and exterior in nice shape. Car was repainted by the previous owner. I've owned the car six years and ...
Today I sold my 1986 300SE W126. It was the right decision to sell, but that doesn't mean I'm not going to miss the car. It wasn't the nicest 300SE in the country, but in ...
