Troy Bilt Mustang 54 ZRT Hydro Gear question

[Skwerl58 737]

A church friend gave me a 2014 TroyBilt Mustang Zero Turn 54" mower that some barbed wire had gotten wrapped around the hydro fan shaft. I got it running and cleaned the barbed wire from the hydro gear shaft. Runs good but is leaking at the shaft below the fan. I looked for seals for the shaft but factory schematic does not show one just a ring and washer. I am going to drain the hydro fluid and replace with the correct oil, any ideas how to repair the leak.

[sjoemie himself 3,072]

Best way I can think of is measure it.

Measure the ID, OD and height/thickness of the bore where the seal is supposed to go. Then go to a tractor supply store or look online using your measurements.