I have a whirlpool washer, I replaced the outer tub and the drive block, but it now doesn't spin. It drains the water, I can hear the motor come on, and feel the vibration . The switch is fine. I looked at the couple, but did not take it apart. The clutch looked fine, sanded the pads and case. Still no spin cycle

When you replaced the drive block did you look at the two "ears" that it fits onto on the shaft? If those are worn down or not mated correctly, it would give you this problem. Just remove the agitator and inner tub again and check the mating of that drive block.