I have a 9n. It has been running great but this last time I tried to start it I was able to fire it up briefly and then it died. (this is pretty typical- I generally have to fire it up a couple of times and nurse it with the choke until it stays running) However after it died it wouldn't even turn over again. No clicking, nothing- like the battery cables came disconnected. However, I checked the cables with a volt meter and I have power to the tractor and to the starter. It is not in gear and the mechanism the starter button seems to be working (I checked it with an ohm meter) Is this a solenoid issue? I'm pretty sure the starter is good because all the brushes are pretty new but how do I check the starter if I take it off the tractor?