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Lately, while working on some PT motors, I've noticed that the gears on some are very tight on the shafts, and prying them off can break off the shaft nubs. I was working on a Chattanooga 5826 GP-20 for a customer in the shop, and it was locked up solid, so I started gently prying on the gears after twisting them. The large gear shaft broke in half first. Then I took off the gear box cover, removed the 3 axles, and tried prying both of the remaining gears off, and both THOSE shafts broke as well, leaving nubs inside the gears. Looking at the remains, the shaft ends look crystallized, not smooth. While I've never seen the motor housings themselves crack, it seems that these little gear shaft nubs are prone to brittleness over time, and seem to expand and freeze the gears. This is not the first one I've had this happen to. Anyone else experience tight gears on their PT motors? I imagine if I had access to a machine shop, I could drill and press in shaft inserts to fix the housing, at some cost. called the customer, and he said don't bother repairing it. Which is too bad, as I freed up the armature and had the motor itself running nicely. Oh well. I did fix his older Mantua Penn Central F9 with MU-2, needed cleaning and some oil, then ran nicely up and down the test track. Another old Athearn F7 was also repaired, cleaned oild, and running well by the end of the day today. So I at least got one Mantua saved and back in service again. Jerry in VA Originally posted by AMC_Gremlin_GT - November 08 2015 :  6:22:44 PM