1985 Mercedes-Benz W123 300 D review from North America

Radiator, Clutch Fan, both half axles on the rear, Timing belt, Tensioning bolt on the Alternator, AC compressor, AC Evaporator, AC Valve, All fuel lines, doors didn't lock, all door vacuum lines had to be inspected and faulty ones had to be replaced. Rear power windows had to be repaired (2 faulty switches, 1 faulty motor) RPM gauge sensor was fried- (still need to replace) Cruise Control is jerky (feels like your riding a horse- suspect either ground or vacuum) Tail lights don't work correctly- (Which is probably related to the Cruise Control problem- since Cruise control ground goes threw the tail lights on these cars)

I bought this car for 1900 on eBay and had to drive 700 miles to get it, it drove back like a champ until the belts started squealing at the 50 miles from home mark... Which really brings me to my ONLY two complaints about the w123 series from Mercedes;

There Factory Radiators have the standard metal core, but instead of having metal tops and bottoms, they used plastic. So over the years - plastic gets stiff and brittle. What caused my belts to squeal, was there was a radiator failure where the intake hose mates to the Radiator housing. This lead to water being sprayed on the belts which lead to the belts squealing. It was a hairline crack so I didn't catch it and assumed the belts where loose (Which the alternator belt was) But I couldn't tighten the alternator because the fancy tensioning bolt needed was stripped. (Makes me miss the ol'fashion tension bolt and crowbar...) Replacing the bolt cost me $65, the after market radiator cost $186, correct Mercedes fluids cost me $10- so my first repair on the car cost me $270ish. (Factory Radiators can cost up to $500, the Nissan all Metal versions (which avoid such failures) cost about $250)

Now that was the worst thing that ever happened to me with this car. Everything else was simply a nuisance. These old 617 Diesel Engines where set up for ease of maintenance in most cases; the constant clogging of fuel filters due to the fact the old fuel lines where disintegrating from the inside out was a simple matter to replace (My record time for exiting the car, replace filter, re-enter and start the car was 97 seconds). When I finally figured out it was the fuel lines and not a dirty tank- the correct repair of changing all lines only took 30 minutes. (Your return lines from the injectors back, need to be bought online- Diesel Giant has the correct parts)

The AC repair on these cars is amazingly cheap, you can replace all parts minus hoses for right under $200, my old '83 Toyota Celica was $500.

The interior of the car is roomy, the seats are all comfortable, with the climate control system being more than up to the task of pushing the air to cool or heat your passengers in the back. And if your AC doesn't work, the Moon Roof makes a great way to cool the car a'la natural.

The car corners and handles well. Its only black marks would come in the fact that it isn't fast of the line. But since Diesels are normally long haul engines and not 'off the line' ones, makes that a moot point.

The safety ranking of this car would have to be right up there with the best of today. I would be comfortable with my chances of hitting anything under the size of a semi or a train, and living to tell about it.

The durability of the car and engine are legendary, while I would never pay $1900 for another one of these in the same condition as what I got this for, I wouldn't trade the one I have for anything. Even thou mine was neglected mechanically for 5-6 years, (Which would be fatal to most cars) it came back from it strong. Engine blow by and consumption was cured with oil changes every 3000 miles with 20% Lucas Motor Oil) So I imagine this engine well go for 500,000 easy before I need to overhaul it.

A added bonus to owning these cars besides Diesel being cheaper then gas right now, is that with a 50/50 mix of Strained Waste Vegetable Oil (WVO) you can run without any modifications (not recommended if your temps dip below 40) Don't know what to do with your used motor oil after an oil change? Strain it and dump it in your gas tank. Temps where your at above 90, dipping into the 80's at night time? Feed the thing straight strained WVO. It'll drink it and like it. Of course if you want to do that, I'd recommend you read up on it before doing it-

On closing you may look at the things I've had to replace and repair, but take that with a grain of salt. These are 22+ year old cars. All of the w123 series. Initial maintenance costs are always high on older cars, but these well pay for themselves if you stay on them.