Oct 14, 2013 update to the Mercedes-Benz 300SD project car

A New Life

Our 300SD tows like a dream, which isn't surprising considering it weighs 3600 pounds.
The Benz has enough ground clearance that a jack isn't necessary. We used a few ramps just to make life easier.
The oil filter is massive, as is the oil capacity. We buy oil in 2.5 gallon jugs.
A cheap set of A/C gauges showed that the car was losing freon.
First, we tried washing it. Then we realized it didn't look any better afterwards, and paid a professional.
A fresh (used) turn signal replaced the broken one that was on the car.
Replacing the Odometer gears was straightforward–the process is exactly the same as in an E30 BMW.
Installing the trailer hitch took a drill and a few hours, but it wasn't hard.
Shortly before leaving, we tested the glow plugs. One was bad, so we changed it.
The 300SD is a natural in the wilderness.
Did we say wilderness? We meant lift. Our brakes and wheel bearings finished wearing out between our home and our destination. We spent a few hours changing them.
We couldn't figure out how to move a set of wheels and tires without our truck. Then we realized just how big the trunk really is. Wow!
Who says you need a truck to tow? I expect lawn companies to make the switch to Mercedes any day now.
Oh, and it carries a bike easily, too.

We call him ‘Otto.’

In our last update, we had the transmission in our 1984 Mercedes 300SD rebuilt. We anxiously awaited the day we could pick up our blue beauty, and about a week later it came.

We hopped in, went for a drive, and were still in love with the car. It still had some glaring issues, though. Namely tires, or more specifically tire tread: only the spare tire had any!

So, we logged on to TireRack.com and bought a set of 4 General Altimax RT tires in 205/70R14. Keen readers will notice that that is a “plus 0” upgrade, proving once again that this is a purebred racing machine. The price, shipped to our door? $297.68–yes, someone who works at a sports car magazine actually bought tires. Everyone else on staff is making fun of us.

Why these tires? We’ve been really happy with General tires in the past (like the Grabber AT2s on our Trooper), they were cheap, and they were well reviewed. We’re happy with them, and they do everything a tire like this needs to do.

With the car rolling down the road smoothly, it was finally time for an oil change–who knows when it was last done. We used 10w-40 Rotella T and a filter cartridge from Autozone. While we were in there, we also changed the air filter (the old one was black), checked all the fluids again, and threw another can of freon in the A/C system. The car will need a new A/C compressor at some point, but it works fine for now. We also changed a glow plug that wasn’t working any more.

Next, we thoroughly cleaned the car. Or, rather, we paid to have it thoroughly cleaned. For $100, it was buffed, the interior was detailed, all the varios goos and stickers placed all around it were scraped off, and the engine bay was made like-new again. Yes, it was wasteful to spend $100 on detailing for this car. But when your girlfriend tells you it has to be clean (and you suck at cleaning), you’ll pay it.

We also replaced a few broken items–a turn signal and a mirror–with junkyard items. This cost about $25 and fixed the two most-noticeable issues with the car. We also replaced the odometer gears, as we wanted to keep track of fuel consumption and it annoyed us that they were broken. We bought replacements from OdometerGears.com, and they installed in a few hours.

We had a transmission, tires, clean oil, and a clean car, so naturally the next step was to drive it– a lot. We had planned a camping trip in our Trooper, but it was tragically disabled just a few weeks prior. The solution? Just take the Benz! But before we could tow a camping trailer to South Florida and back, the Benz would need a hitch and a trailer wiring harness. We bought a $200 hitch on Amazon, and a wiring harness at Autozone. After a few hours in the garage, we were good to go.

And, surprisingly, it went great! The Mercedes towed our little trailer to South Florida and back, though we did stop for a visit with Rennie at Redline BMW Performance. The reason? He’s both an old friend and an excellent parts source, and we had finished wearing out our brakes and our front wheel bearings somewhere between home and Pompano Beach. The replacement parts for this cost just over $200, lunch, and a few hours of work at his shop changing them. We threw in a little more freon somewhere along the way, too.

Other than those issues, though, the Benz did great. It even earned a name: Otto von Bismarck, after the famous German leader and the largest battleship Germany ever built. We call him “Otto.”

Once home, we didn’t stop driving the Benz. It’s a great daily driver, and (as the pictures show) it’s practical, too.

We now have $3150 invested (squandered?) in the Benz.

This project is being funded entirely by a college student who works one part-time job. Any deviations from this funding scheme will be noted in the updates.

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Comments
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Jerry From LA
Jerry From LA Dork
10/15/13 11:42 p.m.

In my old neighborhood, we used to call that a "three-body trunk."

belteshazzar
belteshazzar UberDork
10/16/13 9:31 p.m.

observed mileage?

Tom Suddard
Tom Suddard Associate Editor
10/17/13 8:29 a.m.

Observed mileage: 21 in the city, 27 on the highway, 24 towing the trailer on back roads.

LawrenceRhodes
LawrenceRhodes
11/14/13 10:27 a.m.

This is the most technologically advanced Mercedes of its time. Using the same motor as the W123 series it has better 0 to 60 times & better fuel economy. This was accomplished through better aerodynamics and it is considered the first Mercedes to thoughtfully consider aerodynamics as a solution to fuel economy and performance. It is also ideally suited to running vegetable oil as a single or double tank conversion.

redstack
redstack Reader
9/12/15 10:21 p.m.

Any updates on Otto, is he still in the pack?

Tom Suddard
Tom Suddard Associate Editor
9/13/15 11:06 a.m.

Unfortunately not—his transmission died a hero's death when it broke in half.

He has, however, been replaced by The Commissioner, a 1987 300sdl.

Esoteric Nixon
Esoteric Nixon UltraDork
9/13/15 11:20 a.m.

Tom, weird question, but was the HVAC system in Otto as complicated to work on as the one in the 87, or were you lucky and both work without issues?

Knurled
Knurled UltimaDork
9/13/15 11:47 a.m.

Tom Suddard wrote:

Unfortunately not—his transmission died a hero's death when it broke in half.

Good thing you didn't call it Brakes, then.

Knurled
Knurled UltimaDork
9/18/15 9:37 p.m.

In place of old life?

Unscarred by trials?

(okay really I am just replying to this thread because A: Evan Williams and B: trying to un-bold the thread)

Tom Suddard
Tom Suddard Associate Editor
9/19/15 8:15 p.m.

In reply to Esoteric Nixon:

The HVAC system in Otto was FUBAR, and I left it that way. I threw a ziptie on the vacuum pod behind the glovebox to keep the side vents working, and drove it like that.

The '87, thankfully, has a properly working HVAC system.

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