The internet cited 'Egg shaped belts" as a clear sign of pending failure due to heat, too much tension. I have seen a lot of industrial belt failures on variable speed drives, Varidrive is the most common industrial drive ( electricians get called on everything and have to prove it was not an electrical failure but was a Mechanical failure). Varidrive uses the same/similar mechanical sheave technology as CTV's. VariDrive belts will egg shape but more commonly distort and not lay flat because one side is longer than the other, edge wear , cord showing , belt has a dome in it. Some if not all CTV require high heat belts . Inspect sheave for groves ...wear. Hope that helps

I am going to wrap the commutator in fine sand paper and turn with the sand side against the brushes to seat them. The brushe appear to seat. but the sand paper ill show up gaps. The magnets are held in with screws...But haven't got the loose as yet.