1982 300sd, need general advice - PeachParts Mercedes-Benz Forum

websitedude · #1 05-07-2003, 07:53 PM

Just bought this '82 300SD for my son's fist car. As I'm told, they run forever right? Anyhow I've got a few questions. First, what's different with the SD that the D doesn't have? It seems to run decent, I'll change the oil, any other cheap maintenance tips, common things to check etc? Are power window motors easy to replace? thanks,
Dan

sixto · #2 05-07-2003, 08:16 PM

The SD is bigger, has electric seats and a dedicated electric pump for the door locks. Everything else is about the same as in a 300D.

The window motors aren't difficult to replace, but having skinny arms and two elbows per arm would make the job easier. In most cases the motor is good but the platic slider that lifts the window disintegrates. less than $10 for the part and a robust nautical vocablulary should see you through the job.

If the rear sags, new subframe bushings will improve the ride, handling and tracking. It has the same front suspension as the 300D except for a more complex rear mount for the guide rods.

The ACC system is very similar to the 300D's.

I've never had to deal with a rusty car so I don't know where to look for rust or how difficult it is to repair rust.

Sixto
91 300SD
87 300SDL
83 300SD

86560SEL · #3 05-07-2003, 08:30 PM

That is correct. The SD is a larger car, with a body style like the 380SE/SEL and 500SEL, although a shorter wheelbase than the SEL. As far as problems, I think the blower motors are a common problem. As far as rust, as with any older Mercedes that was a northern car, the floors seem to be the a area prone to rust on northern cars. I live in the south, where rust is not a problem on about any car, but I have heard about this rust and seen northern Mercedes on E-Bay. Other than that, these cars will last many, many miles, especially if well maintained.

dmorrison · #4 05-07-2003, 08:31 PM

Well
Welcome to the world of Mercedes Diesels.
Continue to read the posts on this forum It will teach you a lot about The 126 and 123 Mercedes.
You have a W126 Mercedes with a 5 cylinder Diesel engine.
It is refered to as the 300SD.
The 123 is the 300D (240D and 300D Turbo). It has the same engine as you do. But the body is the 123 body
I will attach pictures of both

Change all the fluids to get you started and the filters associated with them. How many miles? If over 100,000 think about a timing chain change. You can do a search on how to check the stretch of your chain. Do a valve adjustment.

Fluids and filters
Oil and filter
Transmission and filter
Radiator, no filter but use only Mercedes antifreeze.
Brake fluid flush.
Rear differential change of fluid.
Fuel filter change both inline and main filter
Check the fan belts
Air filter

That should get you started.

SD vs D
The SD was the luxury level in the 80's, still is
The D is the bottom of the line car.
Your SD has more luxury designed into it.
Electric seats, Maybe heated,
Larger and wider car.
Leather, usually
Its as I said the Luxury level that Mercedes sold that year.

Changing an electric window motor. In 23 years of owning Mercedes I have never had to change an electric motor.
Switches or fuses to the unit yes. Even mechanical parts that wear out. but never a motor. The window usually has the small plastic slide that is installed in the window mechanism fail. I've done 3 on the daughters 300SDL. The L means 5 inches of leg room in the back seat of the car, vs. the SD.

The Key to the diesel engine is to regularly change the oil and filter every 3-4000 miles. Do this and your engine will last 500,000-750,000 miles. Don't and you'll get 1-200,000 miles.

Dino oil ( natural) or synthetic, You decide. It has been discussed to death here and in the Mercedes Club of America. I personally use Dino oil in my diesels. But synthetic in my SL, go figure!!!

Dave

dmorrison · #5 05-07-2003, 08:31 PM

The 123

Heres a link to an explanation of all Mercedes sold.

http://fly.hiwaay.net/~gbf/mbmodels.html

Dave

tjohn · #6 05-17-2003, 11:33 AM

One quick addition. If you have a problem with water getting into your trunk, check the rear window seal. These often degrade as they age, and will permit water to leak in, causing rust up around the underside of the rear deck. If you're flexible, you can stick your head into the trunk then roll over so you're looking straight up. You may see a tell tale bit of rust.