Sorry to hear about all your problems with this gearbox. I think the least expensive way out would be to toss the old gearbox and get a GruBee stage II gearbox. You would have to use a 1 mm shim for the output shaft of the motor if it is a 142-F. I have the same setup as you but nothing has broken - yet... Did your gearbox come with the vented fill plug? If so, there is a newer (improved?) model with no plugs and angle cut gears for the clutch bell and main gear. I have no idea if the gears are any stronger, but they are supposed to be quieter and the box is a direct replacement for the one that came with the Huasheng 142-F. It would cost less than the GruBee, but the GruBee has been around longer and is probably more reliable.

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