Distributor shaft vertical movement
 

I attempted to search the previous post and found some postings on distributor shaft movement however cannot find a tolerance figure or something that would tell me how much movement is considered normal or OK. As mentioned in a previous post, three contact points in my distributor cap have small gouges from rotor contact. The rotor contact point is also wore unevenly on the right side and burnt. Attempting to identify if this is the result of the distributor cap not being seated correctly or or if my distributor needs to be rebuilt. The distributor shaft has approx. 1/16 inch vertical movement and very slight horizontal movement (way to small to measure). I telephoned a rebuilder today and he informed me that the shaft should have zero vertical movement and that the distributor needed to be rebuilt. Apologies of the question is a silly one. Still attempting to learn from reading postings and forums.

You are looking for .005 of play..or so. The fabric washers fail giving the dizzy the excessive endplay.

"zero vertical movement"
Jesus! Mine moves up and down probably 1/8 of an inch....
and I do have a strange knocking sound now and then, mostly at low idle.

Aaron is correct but let us expand:
The distributor shaft should have minimal axial play .001-.0015" and the lateral play (although taken up by fiber washers to be close to zero) should be no more than 004."or so.

The main source for concern in the early points distributor is the play/tolerance between the rotor shaft and the main shaft in the distributor. There is a small piece of felt under the rotor that is meant to be lubricated during every service but this service has been relegated to an "occasional at best" service and this lack of lubrication causes wear that is very often overlooked.

During a rebuild of this early style distributor it is not uncommon for one or both of these pieces are worn beyond usable ranges.

New parts are unavailable so core distributors with usable parts are the only resource.

Low rpm knocking noises in 911 engines are generally caused by intermediate shaft gear wear or piston slap. It is uncommon for a distributor to be a source of strange knocking noises.

That said: with enough excess play I guess you could have some noise.

Doesn't sound that promising...
I have been ignoring this and several other issues (probably worn valve guides) for a while, but I have a low mileage 3.2 thats going in later this year.
I'm hoping it will stay together for a couple of thousand miles more... Then I will look into it.