Incidentally, had an intermittant hot starting problem on my W123 280E that turned out to be a partly fried starter motor. The motor was apparently a 1.1kW model and too small for the car.
My independent MB mechanic has just fitted a rebuilt 1.8kW motor, the highest power available for the 280E, and now it starts like a dream. Right on the button.
Unfortunately he had to take the exhaust system off to fit the 1.8kW motor in, but it was worth it!
1977 W123 280E