I got a rototiller at the dump. The motor is fine, but it wouldn't shift gears. The "transmission" was a bitch to get apart, but I did it and found rust, as I expected. I'm undecided between pitching it and rehabbing it.
Even with the rust removed, the gears will be very rough and wear quickly, but:
- it would get very little use (maybe an hour or two per year)
- the transmission runs at fairly low speed (900 rpm max input, down to maybe 50 rpm on the wheels)
- it only handles 5 hp
My feeling is that under these conditions the transmission would last a long time and perform normally, if noisily.
Finally, I like to rehab machines, but I don't like to waste my time.
A pic of one of the gears after HCl de-rusting and bead blasting (the teeth are about 1/4" wide):
Bob