I have a rather strange starting problem. My car is a 72/73 280SE 4.5.

After sitting for awhile (this could be a few hours or a couple months) I will turn the key to run wait for the fuel pump to prime for a few seconds, it then clicks off and when I turn the key to the start position I will hear a relay click but the starter does not crank. I can repeat this many times, what solves the problem is turning the key back to off and then swiftly/without stopping at the run position turn the key all the way to the start position. It will then crank and start just like it should. Any ideas?

+I have tried moving the gear lever through its positions, trying to start in neutral, etc. and no change in behavior.

+Also if I am using the car regularly (short trips) etc. I can turn the key to run, wait a few seconds for the pump to prime and stop and then turn the key to the start position and it works fine…but if the car sits between trips for more than a few hours generally you again will have to turn the key more rapidly to start to have the starter engage and crank.

Thanks
Jason