A system for flushing a conduit having an inlet, an outlet, and at least one flow restricted outlet between said inlet and said outlet. There is a pump operative to periodically be turned on and off for pumping a liquid from a liquid source to the inlet, a pressure pulse being generated when the pump is turned on. A hydraulically actuated indexing valve has an inlet connected to the second outlet end of the conduit, the indexing valve including a valve element assembly indexable between a plurality of indexed positions in response to a plurality of pressure pulses, wherein in at least one of the indexed positions, return flow from the second outlet end of the conduit flows through the outlet of the valve to increase flow rate through the conduit.
