could the timer be faulty?

Washer fills correctly and agitates very
well. When the timer reaches the spin cycle it starts very slow and if left operating the tub remains almost full. I chacked the pump and it is operating. I removed the lid safety switch and connected the wires together and the operation remeined the same. After trying everything else I turned the waher off, moved the dial a little and turned it on again the spin cycle worked well and the tub drained completely. This has to be done for both spin cycles and requires standing in front of the washer all the time. Cuould this be a faulty timer or a faulty timer switch? Can the timer switches be replaced?