Help Needed! Auto pilot pinion gear

[Musicaltrees]

Hi… I have an older Autohelm 4000 by Ray Marine. I'm in the Bahamas now and this thing has broken down on me. The problem appears to be with the small pinion gear that guides the belt. see photo… this gears slides over a ROUND stem. Evidently, something broke off that holds this pinion gear tightly to the stem, or post, that is inserted into it. The parts schematic does not show any parts that attached it to the stem that would fit inside that hole which has 2 little "ears" on each side … and I wonder why the hole in the pinion gear has "ears" on each side of the hole… all the other mechanics work, except you can hear it slipping on the gear teeth trying to grab,, but it can't because it is slipping on the pinion gear… something has to be there that holds that gear snug to the post… but I can't find it on the schematic for the life of me… any suggestions anybody?? See photo and schematic attached. If there are no images attached, pls let me know…

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[a64pilot]

Never seen the insides of one, but is there a hole in the shaft this gear slides onto? If so is this hole filled with plastic? I'm thinking there is a plastic rod that sort of is similar to a roll pin.
It's real common for metal gears to be held onto a motor shaft by a steel roll pin, perhaps a plastic pin was used in a similar fashion?

[colemj]

The pin #19 isn't it? From the schematic, it looks like that pin goes through the shaft and fits into the ears of the pinion.

Mark