Date registered: Feb 2010
Vehicle: 1972 280SEL daily driver. 904 Dark Blue with cognac interior. euro 4.5 engine
Location: Williamsburg, VA
Mentioned: 3 Post(s)
Quoted: 34 Post(s)
As the owner of a 72 W108, I am a bit biased. Love the car. I have, however, pretty much touched everything on this car.
Not sure what year your R107 is, but if it is a 450 then you will already know some of the engine issues. If not, check out timing chain stretch, tensioner, guide rails, oilers. Otherwise, the engine is pretty reliable. If you have no experience with D-Jet cars, there are a few components in the system that are hard to find and expensive if you do....but they are very reliable so if it runs good now, that is a good sign.
I've changed to Pertronix for ignition and highly recommend it.
The W108 does not have ball joints, it has King Pins. A lack of maintenance on them can lead to some expensive repairs. The eccentric bolts at the top of the king pins is likely frozen anyway so expect some pain if/when you need to adjust the camber/caster.
My W108 ran hot when I purchased. Much better now with a radiator recore.
Heater switches are an issue, but a larger issue is the heater blower motor not working. This car has two blowers...one comes on with the air conditioner blower switch. The other one (the heater blower) comes on when the top left heater lever is pushed to the left. It should have 3 speeds. If it does not come on, it is a 12-16 hour job to replace.
Rust in all the usual places...headlight buckets, rockers, jack points, trunk wells. My opinion is that these cars don't have surface rust. If it looks like surface rust, it is cancer that goes much deeper.
Window regulators seem to be issues as well. All cast aluminum and they seem to warp and then wear gears badly until they fail.