1972 280sel "HELP"

[awarne]

I just bought this car for my wife to restore and am trying to figure out why it idles high and shakes. It has new plugs,rotor,cap,wires,air filter. Could it be vaccum leak?
Also it seems there is an lack of power when you start from
a dead stop. I am very mechanically inclined and would greatly appreciate some advic. Also at about 20 mph there is a rumble that feels like its in the rear? could that be some kind of U joint or something? Otherwise its a beautiful car. I also bought a manual but it only covers the 6 cyl. I cant even find where the timing marker is.

[hill]

For finding vacum leaks try a spray bottle with water set on stream. The engine will stumble if you spray on hose/port or gasket edge that is bad. As far as the rumble check the center carrier bearing on the driveline. I would recomend just pulling out the drveline then checking it. As far as shaking have you checked the trigger points for the fuel injection? These are located below your ignition points a lot of non Mercedes savy mechanics miss those. Valve adjustment is important to but if it is your first time on this type of engine get a pro to do it or better yet show you. Regards,

[awarne]

Thanks alot for your input. Ill try all of your suggestions