On Mon, 20 Dec 2010 19:45:35 -0800 (PST), oldjag
wrote:

I've got a ~ 50 year old Wagner 5 hp repulsion induction motor that's
been sitting around forever. I decided to put it on a air compressor
I picked up that had a 3 phase 5hp. Supposedly, the motor had been
rebuilt before it sat in storage the last 40 years, and it does in
fact look fairly clean inside and has good starting brushes. I think
it came off a refrigeration unit. Weighs about 200 lbs.
Anyway it sparked on the commutator a fair amount on the first
start, and once in a while during starting it seems to go into
induction mode but then drop back into repulsion mode a few times
before finally staying in induction mode. Current draw is as per name
plate, ie 30 amps at 230V when up to speed and it runs cool. I took
it apart, turned the commutator and undercut the mica. When I
reassembled it still had the same problem. While apart I was
wondering if perhaps shorting keys were in backwards, these are about
100 thin copper plates about 1/4 x 1" long held in a circle by a wire
ring. I put them back in the way I found them. They get pushed
rearward into a shorting position when the flyweights push back two
pushrods that run lengthwise thru the armature. The pushrods also
lift the brush assembly from the commutator when the motor reaches
speed. Can't really see anything wrong...Anyone ever see one of these
motors?
You need a slightly smaller pulley on the motor - it is overloaded on
startup.