My Roper washer decided to quit draining recently. The washer fills and agitates normally but when it gets to the first drain cycle, the motor starts but the water does not drain. The motor hums loudly when this happens and I also hear a slight metallic rattle. When I open the lid, the motor stops but the tub is just sitting there fulll of water. When I close the lid, something catches and it begins to drain normally.

Someone suggested the lid switch was going bad but this confuses me because the motor runs when it should be draining. Any ideas?