Hello all,
I'm looking at purchasing a 1981 300SD with a 5 cylinder turbodiesel. I found this one in the local classified listing and went to look at it today. I'm not new to mercedes, but I'm new to the diesel powered kind.

Many of the electrical features do not function properly in the car. The sunroof begins to open, but doesn't go very far. Only three of the power windows go down, the drivers one is doing nothing, so I'm assuming it's the switch. The seat adjustment only goes forward and backward, but the backrest does not adjust. The car is leather, but has a few minor rips. The passenger side power mirror does not move either. I can live with all that stuff, or find some pieces at the junkyard. I'm concerned about the mechanical condition ....

At first look everything looks nice, like the brakes and everything works. It shifts a tiny bit rough, but it may just need a fluid change. Once I had the car warmed up even at idle the oil pressure was pegged above 3 bar. After I opened the hood I noticed smoke from the dipstick. There is way too much crankcase pressure (I'm assuming vented through the top by the valve cover). Then I opened the oil filler cap and there was a lot of smoke coming out that way. Previous owner said "oh just some blow by". Well I look underneath the car and almost the entire length of the car all the way to the gas tank is covered in a thin layer of oil. I'm assuming this is related to the smoke, because other than that, nothing drips. I noticed that car was running a little bit rough at idle, but that's it. It pulled very strong.

The cosmetics are okay. The trunk has a little dent in it, no big deal really. Paint is good, it's a silverish color. The guy is asking 850 and I talked him down to 700 ...

My questions are
-how serious is that smoke and the oil underneath the car (previous owner states his other car does the same)
-is it worth the 700?
-milage is 280K, will it last a while?

Sorry for all the questions. Thanks in advance

Christoph