ARO PH15F-ASP-STT-A Pump Part Exploded View Diagram & 2:1 Ratio High Pressure Pump Repair Parts PDF Manual. Air Section Service Kit: 637389, Fluid Section Service Kit: 637445-TT, Major Valve Service Assembly: 637390-7 Available. Replacement Diaphragm, Seat, Balls, O-Ring, Seal, Rod, Manifold, Washer, Bolt, Nut, Gasket, Screw, Pipe Plug, Fluid Cap, Motor Body, Plate, Spool, Ground Lug, Valve, Tube, Muffler.