On a 20+ year old Maytag A8520 washer, working satisfactorily, it was partially disassembled for only the reason of cleaning out accumulated "gunk" (of which there was a shockingly large amount) from underneath the agitator. The inner tub was also removed, and there was additional cleaning to be done in the bottom of outer tub.

After reassembly, a test run. Water filled OK. But no agitation or spinning, and there was screeching sound – and a burning smell which I wasn't sure was belt rubber or a motor problem. It was turned off and unplugged shortly after these symptoms were noticed.

Given that all was working well before this cleaning operation, what might the problem(s) be? I should mention that I had to do a great amount of really hard banging with the tub wrench and a hammer in order to remove the spanner ring that secures the inner tub. Maybe all that banging damaged something? I plan to replace the belts, but concerned the problem could go beyond that. "Braking assembly" underneath where belts are? The "transmission" underneath outer tub? Main motor? If you have an experienced guess, I will appreciate hearing it.