Date registered: Sep 2004
Vehicle: 2014 E250 Bluetec 4-Matic, 1983 240D 4-Speed
Mentioned: 3 Post(s)
Quoted: 256 Post(s)
RE: Hi everyone first time here
Check into the Diesel forums here and on ***************** to get a handle on what owning one of these beasts is all about. Really great machines, but after twenty years, you may have a great machine still, with another twenty years in it, or one problem after another. With simple, but regular oil, oil filter and air intake filter changes, and valve adjustments these things can be virtually indestructable.
I would start out with a change of all the fluids in all the systems on the vehicle. Engine oil, brake fluid, power steering fluid, transmission and differential fluid. Use good quality replacements fluids that are "sanctioned" by MB, or a good new synthetic fluid. I use Mobil Delvac 1 in all my cars, as well as Redline transmission, differential and power steering fluids. I use Castrol GT LMA DOT 4 brake fluid.
While you are there, check the pads. They are pretty easy to replace on this vintage Benz. Check the rotors and hose from the steel tubing to the calipers. Note any evidence of oil or other leaks and clean the areas to keep find the source and keep track. It is near impossible to trace an oil leak on one of these once the engine is covered in black gunk. By the way, the engine oil is ALWAYS black, like in 30 seconds after changing oil always.
Check the valve clearances. This is a routine job you have to do if you want long life and decent starting. Buy the wrenches, they are available on Ebay and make the job significantly less anxiety intense. Only worry about the fuel filters if the external inline one looks bad, which is usually an indication of an algae infestatiion in your fuel tank. You need to kill that crap with a regular additive application (some "icide" stuff to kill things that live in fuel contaminated with a littel water, which is unavoidable if the car sits very long) and change the filters regularly until the problem and its residue is gone.
Once free of the living crud, use a good additive regularly. I use Redline's Diesel Fuel Catalyst, but there are others that work fine as well. Diesel is a poorly regulated fuel and in some places when it is pumped out of the ground, well, that is literally what is happening and you get a little extra this and that, and not enough of the other. Find a reliable station and stick with it, or use ones frequented by 18 wheelers regularly. Don't buy fuel (or gas) if you see a fuel delivery truck in the station. That just stirs up all the crud on the bottom of the tank and you get some extra, unwanted matter.
Not driving them can be almost as certain a death sentence as infrequent oil changes though. They love to be driven hard. Once you are clear on having changed the oil and vital other fluids, you are certain the machine's controls are working properly and safely (brakes and steering, especially) take it out and find a hill. A long one. Get it going flat out, wide open throttle, up the hill, and run it near redline for as long as you can. Initially great clouds of black shit will stream and billow out the back. As you clear out the accumulated particlulate deposits in the pipes and combustion chambers, the engine will stop the smoke signal to the EPA and run better. With a turbocharged unit, which yours may be, no smoke is a sign of a fuel delivery system setting in need of adjustment. At wide open throttle the W123 300D TurboDiesel should smoke lightly. Based on the price you quoted I am assuming you scored a W123 with some issues (Ohio usually means salt in the winter which also means body rot). White smoke is not good and you should probably shut her down if you see white smoke. Blue smoke when warmed up is also not good if qualifies for the "billowing" adjective.
Anyway, good luck and really, jump on the Diesel forums. The response will typically be more reliably helpful. Jim