The tub is locked for wash mode. For spin mode the motor reverses and releases the brake and the tub spins. The kit comes with various washers to replace so that the brake will release. If you put too many then the tub won't lock in wash mode and the clothes will get knotted up. Too few washers and the brake will not release. The tougest part of this job is getting that dang clip on last to hold everything in place. I cheat by using a pry bar against the brake spring just to make it a tad easier to get that clip on.