Two factors must be used to determine the maximum length of hydraulic hose you can run from the hydraulic power unit to the submersible pump. On the pressure side friction losses in the hose and couplings will reduce the amount of pressure available to the hydraulic motor. This will cause a reduction in power from the motor and may have an effect on the submersible pump output. On the return side friction losses not only will effect performance but also create excess backpressure that can damage the hydraulic motor and possibly cause seal failure in the motor. As a rule of thumb we recommend going to a larger return hose on running distances greater than 150ft. (45m). Use a larger hose on the pressure side on distances over 250ft. (76m). Also see information regarding the use of case drain hoses (click here).