Distributor Rotor Keeps Burning 82 380sl

HEY I HAVE A 1982 380SL THAT BURNS THE ROTOR JUST BENEATH THE POINT THAT DISCHARGES TO THE PLUGS ,THE CENTER FROM THE COIL IS FINE. I CHECKED THE COIL WIRE TO THE DIST. FOR RESISTANCE AND IT DIDNT READ ANY SO I REPLACED THE COIL WIRE. THE CAR RAN FINE, GREAT ACTUALLY AND NOW ITS HAPPENING AGAIN THE ROTOR IS BURNING LIKE THE SPARK IS COMING FROM BENEATH THE CONTACT ANY IDEAS???:banghead:

Hey I have a 85 380sl thats giving me the same prob I changed cap and rotor twice and even a brand spanking new distrubutor that did'nt do it... So i think the timing might be off (new timing chain) I know its time to change mine. Do you ever hear an occasional rattle at the front of the motor at start up? If so, thats the timing chain failing we should change those bad boys asap!!!!!!!!

***Hey danny*** I made an incorrect prognosis the problem with that distributor is the Gear/sprocket that drives the distributor it gets worn after a while, remove the distributor cap turn the rotor button by hand if it moves at least 1/2" to 1" left or right then the sprocket is worn, but still, dont ignore the timing chain.