Permanent Split Capacitor motor question?

Here's the deal, I have 2 PSC motors, and I have the same problem for both. I wire it up, and I try to run it in ay direction, and I hear a click, but no movement. The motors and capacitors are old, but the wiring diagrams are very clear and simple. There are 4 wires, green (ground) white (common), red and black. In the diagram, the black and red are shown connecting to either side of the capacitor (7.5uF), the white directly to one side of the 120V AC source, and the other side of the 120V AC source connects to either the black or red (depending on whether you want clockwise or counter clockwise motion).

I'm SURE I've wired it correctly, however, I just won't go! Again, I hear it click as it it wants to go, but nothing. Is it the motor, or the capacitor? Please help