Would a bad crankshaft position sensor cause hard starting on my 1985 380SL which runs fine when it is running but is hard to start on occasion. The car only has 75,000 miles on it.

 

The 380Sl doesn't use a crankshaft position sensor. It uses a hall sensor built into the distributor. There is a sensor on the front of the crankshaft, but it is only used as a pickup to use for checking the ignition timing with a tunescope.
It may be that you have a problem with the green wire that runs out of your distributor, but also check and make sure that your fuel pump is cutting in.
Is the car hard to start hot or cold. You may need to get the fuel pressure checked. It is critical with that type of fuel system.