Mercedes Benz repair: 1977 280 SE Mercedes Benz Timing Problem, mercedes benz, noticeable loss

Question
Hello Tim,

I look forward to you advice as to how to solve the following problem with my 1977 280 SE.

The car was running fine until recently it developed a noticeable loss of power and the engine start to vibrate. On the highway it taks a long time to get up to speed, and there is a lot of "pinging" (pre-ignition)going on. I checked the timing and found it to be way off; 50 to 60 degree BDC -may be more. It should be 15 BDC per the spec. I tried to adjust the distributor setting but it max out in one direction and there is little improvement in the timing. Rotating the distributor in the other direction helps somewhat but the engine shuts off just before the distributor reaches the max setting at which point the timing is about 25 BDC.

What to do? I appreciate you advice.


Answer
Well it sounds like your timing chain needs to be replaced.
Remove the valve cover and rotate the engine until at top dead center. There is a corresponding mark on the camshaft at the front directly behind the timing gear. Those marks should be aligned. If they are off the chain should be replaced.