I had a seal go bad on my sequence 4200, and the problem was slow in developing. First some salt creep started to appear on the motor shaft, and got worse over time. Eventually, I started hearing a high pitched squeal...intermittent at first, then becoming more and more persistent. Finally it got very loud, which prompted me to call Sequence. At no time did it leak faster than the water evaporated.
Sequence was great. It ended up that the seal was bad and a shaft bearing got wet and was making the noise. They replaced the seal and the entire motor no questions asked (never even asked for a receipt to establish the purchase date), and even provided a loaner pump while mine was being worked on.