Thanks to everyone who responded to my question, it has turned into quite a large and interesting discussion!
I have had the bearings soaking in a naphtha type solvent for the last couple of days and will let them dry out later today. Successive solvent changes now look pretty clear. The rotor shaft journals look fine. The oilite bearings are located in diecast end bells with some sort of fabric around them to retain the lubricant. I'm reluctant to disassemble them further or remove the bearing shells from their housings for fear of damaging them.
I've decided to use Mobil-1 oil but not to bake the whole end bell assembly because of lack of facilities and the potential effect on the absorbent fabric. I'll just dribble the oil into the holes in the bearing housings and run the motor for while to let it warm up and soak through. Maybe a blast with the hot air gun will help.
The rotor was located axially with a mixture of nylon and fibre washers together with wavy spring washers that look like phosphor bronze. Some of these are quite worn. In his book Stan Griffiths mentions that Tek used to supply replacement teflon washers but I'm sure they would not be available now. However I have found a source of teflon washers of the right size intended for the radio controlled model industry and they should arrive next week. In the meantime the scope is sleeping on its side on my workbench and I'm taking the opportunity to clean the filter and a few more areas.
Incidentally the stator of the motor has a date stamp of January 16, 1964. Electronically the scope works perfectly and is a pleasure to use. It's only needed minor maintenance in the 15 years or so since I paid $100 for it. Not bad for a 55 year old classic!
Morris
