It is probably not economically feasible to use ASDs on wells of 20 horsepower or less. ASD technology may be suitable for larger wells because the cost of the ASD is a smaller percentage of the total cost of the pump and related equipment. In some cases the teeth on the gears in the gearbox on a beam pump unit become worn down, and there is a loss of efficiency. Depending on the design of the gearbox, it may be possible to reverse the direction of rotation of the pump motor and thus utilize the opposite sides of the gear teeth, which, generally, are not as worn. If your gearbox will allow for this operation, simply interchanging two of the three leads on the pump motor will reverse its direction.
Loose belts can reduce the efficiency of a beam pump.
Tightening belts can help the pump operate more efficiently. Worn belts should be replaced with the newer, high-efficiency belts. These belts do not slip as much and work better. Higher initial costs for the belts are recovered in the energy savings they achieve. This is not the case, and if the fit is too tight, the drag on the polished rod will result in inefficient operation.