That's a great machine! The clutch on the handwheel is gummed up. To get a better grip on the clutch knob, you can push the machine back against a counter, with the handwheel facing you. Loosen the set screw. Twist the center knob off, as you push against the counter. Sometimes I use a rubber gripper -- like you'd use to open a tight jar. If that doesn't work, I use those big plumbers adjustable wrenches, with the gripper still in place so the handwheel doesn't get damaged. When you get the knob off, there's a ring underneath it with nubs on the inside and nubs on the outside. When you put it back on, the nubs on the inside need to bump outward. If you're brave, you can loosen the belt with the hex screw below the lower pulley. Pull the handwheel off and clean the gummy stuff off. A squirt of WD-40 won't hurt the shaft, and works very well. Then I squirt some WD-40 on a flannel rag and clean the center of the handwheel with that. Also clean the washer (if it has one) and back of the center knob. Put 2 drops of oil on the shaft and put it back together. Remember that the ring goes on with the center nubs bumped outward. If, when you screw the center knob back on (and tighten the set screw), it doesn't loosen like it should, remove it and turn the ring one position. Try again. This machine has either 2 or 3 nubs in the middle -- don't have one here in front of me. It's a matter of trial and error to get the ring in the right position. Tighten the belt -- most of these with the hex screw are spring loaded, so you can't go wrong. Some others have the big screws behind the lower pulley that are a pain to get to.