Piston Slapper, you really stick with a puzzle, don't you! I really appreciate that!
That is a possibility. I've taken a lot of things apart before, and what bugs me is even if the mechanic was very good, and used all the right wrenches not to leave a mark on the bolts (which is possible), the fittings were all fairly stuck. I mean, not just tight, where they loosen with an even torque, but stuck.
By stuck, I mean they loosened with a "crack", like bolts and fittings that have been together for a long time without being disturbed. They loosen with a big "crack" and then regular loosening torque.
I may be wrong, but this is why I'm not sure it's been touched.
As you may have guessed by now, this is not a money making mower for me. I plan on mowing with this for the rest of my life. Plus, I like taking things apart, so while I've already got it partially apart, I'm going to take the wheel motor apart. For $53 bucks (seal kit), why not? It'll give me more working knowledge of the mower, and then I'll know for sure if the system is really clean and possibly get more clues.
My only problem now is getting a monster 1 1/2" socket for the hub nut! I'll report back what I find.