On Sun, 13 Jan 2008 19:57:28 -0500, Bob Engelhardt wrote:

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
http://home.comcast.net/~bobengelhardt/RustedGear.jpg
Waddaya think?

I'd run it as is. Worst case you're without a machine if it breaks. If
you toss it now, you're out a machine regardless. All you're out is
reassembly time and a few bucks worth of gear lube. The pitting is
pretty fugly but, the high spots will wear off down to the point where
there's enough contact to handle the load. You'll have a bit more lash
in the geartrain than spec but, like you say, low duty cycle, low load.
And it's low risk, it's not like you're fixing an airplane or
something... When it blows, I don't think it'll be from pits on the
gears.