RonMar
Elite Member
Still got the old filter can? Put it back on and see if the system operates like it used to and you can purge the air out of the system. As mentioned, the suction side should use a strainer(metal mesh element, 150 micron). Hydraulic pumps are great at making pressure, they don't like making vacume to suck in fluid. If the filter you put on is too restrictive in addition to causing cavitation, the added vacume on the suction line will also cause air to be drawn in at every possible place between pump and filter(weak shrunk cracked "O" ring on pump housing, loose pipe union).
