Received a * used* Swisher ZT 2660 26hp in October of 2010 has 50 hours on the meter. First 2 or 3 cuts all went fine last cut of the year when the mower would contact grass / leaves the blades would slow, then stop cutting, motor still sounded fine. The belt does look a bit worn. Ideas????

Is the belt slipping? If it's slipping you'll notice it, because it'll smoke pretty soon. If, as you watch it under varying load, it slows down with the blades then the belt is fine.

If it's not the belt then it's going to be the electric clutch that drives the belt. Get your voltmeter out and tap into the wires that go to the clutch, watch it as the mower runs. Anything under about 13V and the clutch may slip. If the voltage is good then the clutch is worn out. They don't cost too much, I'm pretty sure they're well under $100 still.

Make sure the wires that plug into the clutch are making a good connection. You want to check the voltage between the switch and clutch so that you're also checking the switch- if it's got a little crud in it, or a bad connection farther up the line, it can cause the clutch to slip, and you'll see this as the voltage dropping.

lp