I have a Hayward 3/4HP Superpump that is starting to get noisy. Since we pay about $0.30/kwh, the two speed pumps looks attractive. Can I upgrade this pump by just replacing the motor and the timer, or should the whole thing be swapped out? The pump is used for a 20k gal chlorine pool with one skimmer, blocked main drain, two returns, and a Hayward EC65 DE filter. All plumbing is 1.5"