This is my first post. I have a question about play in the distributor shaft. First, the particulars:

1962 Chevy K10
235 cubic inch L-6
Pertronics electronic ignition

A few weeks ago, the engine began to gallop at idle. It idled so badly that it would die. I suspected idle mixture (after all, the gas tank is 64 years old, there must be some junk in there). I tried adjusting the idle mixture and removing the mixture screw and spraying carburetor cleaner into the port. Then I rebuilt the carburetor. None of that moved the needle.

I replaced the distributor cap, rotor and plugs. No help.

I want to check to see if the centrifugal advance weight springs are intact, but I thought I would inquire about slop in the distributor shaft, first. I can move the shaft "some" back and forth. I could put a dial indicator to it, but without some idea of tolerance, that won't be of much help. I have a [/i]1960 Chevrolet Truck Shop Manual[i] (Chevrolet Motor Division) and the '60, '61, '62 supplement, but cannot find anything relating to my question.

Does anyone know how much play is tolerable for this distributor? Since I am not using points, what impact might that have on tolerances?

If anyone has wrestled through a similar scenario, please feel free to suggest other possible sources of the trouble.