Hello and thank you very much for taking the time to reply!
I think you're bang on with what you've said. I got in touch with Sedgwick many months back, by email and phone (they never replied to any emails despite asking me to send pictures and details on my issues through by email!)
Anyway, they weren't able to help as they didn't have any manuals for machines of this age. The most they could say was that the spindle assembly, which I sent them pictures of, looked to be correct.
To detail the issue I was having, I decided to replace the bearings while I had the top off the saw to replace the drive belts, which were split and worn. I went to a specialist bearing shop near me with the old bearings and got replacements, which were, as you rightly predicted above, much more expensive than I expected! On reassembly, the whole spindle would bind when i tightened the pulley holding nut on (even just to finger tight!). I disassembled and reassembled numerous times to see if I was missing something or just putting the thing back together incorrectly (hence the request for a manual). Eventually I decided to put one of the old bearings back in, the one adjacent to the pulley, to see if it was an issue with my new bearings. This yielded slightly more success. With the pulley nut moderately tight I was now able to turn the whole spindle by hand, although there was still a fair bit of resistance that seems more that it should be. As this was the best I could get it and the other old bearing was knackered during removal, meaning I couldn't reassemble to 'untampered with condition', I stuck with this solution and put the new belts on and returned the top and motor to the cabinet. The saw runs and seems happy enough to my inexperienced eyes. Perhaps I have the added bonus that it stops nice a quickly! I am annoyed I didn't just leave the old bearings in and just replaced the belts, but hey ho a bit late for that.
If anyone has any ideas why I was getting this binding issue i'd love to hear them. The best I can come up with is that the face of the new bearing was a slightly difference design to the old one. When studying the face of the pulley it seemed to have small ridges and depressions that lined up with the profile of the old bearing. On reassembly with the new bearing these 'wear marks?' were then contacting with the face of the new bearing and locking the assembly? It seems like these faces shouldn't be close enough to contact anyway and perhaps I was missing a small spacer or similar between pulley and bearing?
I am very annoyed I didn't take pictures on initial disassembly of the spindle, although I did take a close up picture before disassembly and, on comparison of these, the gap between the inside pulley face and the bearing housing looks to be identical to my now reassembled spindle. Sedgwick also said the spindle assembly looked to be correct in the pictures i sent them.
I am a bit lost, but the saw seems to be working well and i'm not overly keen on removing the top again! However, I'm interested to know if I am a total numpty and missed something that was staring me in the face. Happy to upload some pictures if anyone is interested in having a look...
thanks again and sorry for the long spiel^,
Sandy