I have a 401 that was really gunked up - I'm not sure where I bought it or what I paid but I'm thinking I over paid if I paid for it at all... They should have paid me to haul it away... The motor on this one would spin freely with the clutch dis-engaged. Phil tested the motor and the wiring. It is fine. The motor would go then keep getting slower when the clutch was engaged. I cleaned and cleaned but figured it either had a bent something which I couldn't see or there was still some gummy in there. I finally took off the cord holder and dug down in there after that gear - it is the same machine the kidos helped with - see my QB pic on the left - I was distracted at any rate. Anyway I pulled the cord widget off and dug out oil, fluff, hair or what ever was in there. It started moving better right away - I figured if I did a half job I better go over the whole machine again. I removed the cam stack and cleaned some more. Some how I managed to pop off the spring that goes on the zz and had fits getting it to stay on - finally got out the pliers and bent the thing a good one. Then I wasted a bunch of time trying to find the Tri-flow grease... in plain sight... I found a very screwed up tension in the bobbin area - took me awhile to get it right. The upper tension didn't want to adjust so I swapped it out for another one since this machine is sold and the buyer is coming Wednesday. I must have spent a good couple hours on the tension problems before I figured out the hook had a burr. DUH It seems to be ok now. I need to print out a manual and then do a swatch now that I think it will do a swatch.