The flat drive locomotives with the clutch gear axle rarely have issues with the axle gear in my experience, I have had many many in terrible condition (like have been in the dirt or sand pit) and they rarely break that axle gear or get a weak spring, the weak spot for these locomotives is the motor spur gear which can crack and cause loss of drive.
They are a noisy but very reliable drive unit.
They are a noisy but very reliable drive unit.
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