Replacing a seized bearing , no problem there. The gearing is a helical pinion on the motor shaft driving a large spur wheel. There is no trace of grease in that "gear-box" , why no grease ? because helical tooth-form ? Pinion is steel and spur looks like nickel plated steel
-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on
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