Looks like the gear set is in a closed cycle, no net motion. Check if one of the pins is mis‑spaced or a gear’s teeth are worn so the chain of forces just loops back on itself. A small shift or a loose axle can break the loop. Try nudging each gear a fraction of a tooth; if one steps out, the whole thing will unwind. Keep an eye on the center holes—sometimes a hidden screw is the culprit. Good luck, and don't rush; patience often turns a stuck loop into a smooth dance.

Sounds like a plan. Keep your tools sharp, and remember, the quietest tweak often makes the biggest difference.