Need help - Lionel 164 log loader (6-12915) gear box jam - FIXED!

Hear that clicking sound when it does run? That's your clue- that sound is a cracked gear!!! the teeth spread from the crack and then do not line up to the mating gear.

Well known condition that can happen. This is the failure in many gearboxes in accessories in this hobby using these Nylon gears.

Most of these use 0.5 modulus gears, so buying an assortment of gears and finding one in the pile with the same number of teeth can often be a replacement when parts are no longer available https://www.amazon.com/JISTL-P...uction/dp/B00V66YJQI

@Vernon Barry thank you. Upon further inspection, you are correct. The gear has cracked. I didn’t notice it from the top, but it is apparent front the side.

The gear in question is the top of the spring clutch duo. I’ll try looking around for that.

After some searching, I’ve learned that finding that particular gear, with the clutch bumps on the bottom is proving to be difficult.  My plan of action is to repair the gear.  I've seen where people are able to repair gear teeth using superglue and baking soda.  With the crack's orientation, I  plan to file down a tiny bit around the hub, and superglue a carbon fiber ribbon around the hub.  I've ordered the carbon fiber ribbon and will report back if it works.

To close the book on this - the carbon fiber ribbon and superglue did the trịck.

The hub has a relatively tight tolerance with a neighboring gear, so removing some material is necessary.

i used a drill as a lathe, and filed down the hub by about 1/32 +\- of an inch. 8 then dopped some super glue in the crack and to attach one end of the ribbon. Once that was holding, I wrapped a couple times around the hub, adding superglue as I went, pulling it taught. I did the same with a narrow strip of ribbon on the other notched hub (clutch end). After the superglue dried, I used the drill as a lathe again to sand it smooth and cleaned up any glue drips.

i used a spacer between the clutch gears so I didn’t accidentally glue those together.  

It worked like a charm. I added fresh grease and now the gearbox is turning under the power of the motor.  Hope this helps anyone experiencing this issue.