@lewm @noromance the inner platter is not spinning freely! So - will lift it out and lubricate it - I think?
lewm you say "Take the whole thing apart. Clean and relubricate the bearing. Check that platter spins freely. Make sure belt fits snugly around pulley and platter. Etc." - I have no experience working on TT's. I surely understand now that the inner platter needs to spin freely. I do believe that's the issue and as you said, the motor intermittently overcomes it. Sometimes a push to the platter will help it along, other times not.