In between rear wheels under engine plate. So on your back under engine. I personally would jack up mower with jack stands then get under it. If you look closely at diagram it is connected to one of the idler pulleys of the drive belt.
Thanks again. I got the mower up and on stands after I got home. I was able to find the spring and it was still properly attached. I was very much hoping that this would be a cheap and easy fix, despite that not being how it feels...
Get some one with a strong torch to verify that the shaft on the pump is rotating.
Also check that the bypass valve has not managed to open.
Check the level of the oil in the pump reseviour
By torch were you referring to a light because of my comment on no more daylight yesterday evening? When I got the mower up in the air earlier I had someone try to engage movement while I was underneath and I saw no motion from any pulleys/shafts. Excuse me if I'm just clueless, this is new territory for me. I do not have an accessible reservoir for transmission fluid/hydraulic oil (that I'm aware of). I was under the impression that I had to remove the transaxle to check/fill/replace that stuff on the residential Toros? I'll do a search to find the bypass valve, check on that and get back to you. Thank you!
Edit:if bypass valve refers to the controls below the motor that you slide to allow the mower to be pushed, that was my first check and they are in the proper positions.
Additional info (for what it's worth): when I messed with it today I noticed that my left side drive handle has considerably less resistance than usual when coming out of park into neutral and one side makes it all the way forward, slowly, after the handles go into neutral. This was never the case before the issue the other day. The mower is in the middle of my yard at the moment, I'm hoping to get help to load it from my buddy tomorrow and haul it to my uncle's welding shop so I can have a better area to get this figured out.