hey everyone im new to the mercedes world. I just bought my very first 1982 Mercedes 300SD. from a gentleman who inherited it from his mother-in-law after she passed away. Its got 186,000 orgional miles on it and seems to be in very good shape. Some of the interior door panels need to be replaces and two of the window motors need to be replaced but other than that is wonderful. the transmission shifts a little hard which i think is due to the fact they only drove it around the block every once and a while. this is really a noob question but what kinda problems/complications can i look foward to with this kinda car.......any advice, info, comments on anything about owning one of these cars would be helpful. thanks

 

I decided to put this at the top. I do not know your experience with Diesel Engines so I will write as if you have little experience.
You will need to know this if you run out of Fuel or are not careful when you do a Fuel Filter change. That is how to bleed the air out of the Fuel System.
To bleed the Air out of the Low Pressure Fuel Supply System you pump on the Hand Primer (if an old style you unscrew the **** and pump up and down and screw it back in when done; new style just push up and down on it) until you hear a buzzing or sort of squeeling noise come from the Fuel Injection Pump. However, continue to pump to be sure. This bleeds the Air out of that portion.
To bleed the Air out of the High Pressure System (the part that provides the high pressure to the Injectors) you loosen the Steel Fuel Injection Line Nuts up at the Fuel Injectors on the Cylinder head (17mm). You Crank your Engine until Fuel comes out of all of loose nuts. Tighten them and attempt to start.
Air trapped in the High Pressure System will compress and not allow the Fuel to move to the Injectors; and, is difficult to get out (you can kill a Battery and stress your Starter) unless you loosen the Nuts at the Injectors and give the Air a path to bleed out of.

See if there is any paper work indicating what type of work and maint. was done on the Car.
Unless you have documentaion most previously owned Mercedes need a Valve Adjustment due to the fact that as the Valves wear the clearances become tighter and tighter (no Hydraulic Valve lifters in your Engine).
To other neglected areas are the Fuel Injection Pump Timing and the Fuel Injectors.
Take a look under the Rear End of the Car at the rubber Boots on the Axles.
These cars do not have U-joints on the Drive Shaft they have Rubber Flex Discs; take a look at those to see if the rubber is shot.
Some folks say when diagnosing Automatic Transmission problems you should start with checking the Fluid level first. If that is OK and you are haveing shift problems try a Filter and Fluid Change.
Harsh shifting can be caused by the Vacuum Valve adjustment; Vacuum Valve located on the back top of the Fuel Injection Pump. Or, the harsh shifting can be due to transmission wear.
Take a good look at the Oil Cooler Hoses. If they are seeping; plan on changin them but read the DIY on that first as it is possible to damage the threads on the Oil cooler.
If the Hand Primer on the side of the Fuel Injection Pump has a shiny Aluminum Body plan on replacing that as when they get old they become a source of air leaks.

 

thanks guys all of this is really helpful...im trying to located a chilton manual so i can start to learn the ins and outs of my new car. i had the oil changed in it the other day and that seemed to help her out a bit and i put a new air cleaner on cause i think it had the orgional one from 1982 ( jk ) i found the owners manual and the service record books in the glove compartment and it seems the little lady that owened it took it to the dealership at its suggested intervials by mercedes......so i guess im just gonna continue to work slowly on restoring her. i posted another thread up about that glowplug questino any info on it or anymore info on these is very helpful guys....thanks a million