HHD Series Heavy Duty Hydraulic Cylinders

55 Maintenance, Service & Installation Specifications and prices are subject to change without notice or incurring obligations. Tel: 352-373-3578; Fax 352-375-8024 • email: service@fabco-air.com REPAIR INFORMATION PISTON REPLACEMENT 1. To remove Loctited® piston from rod, heat piston and rod to 450 degrees. 2. Using a spanner wrench, remove piston (while hot) by turning counter-clockwise. 3. Allow piston & rod to air cool before cleaning and reassembling. 4. Clean threads of piston and rod with Loctite® cleaner and de- greaser. Spray threads with Loctite® #7649 primer and allow to air dry (DO NOT BLOW DRY). 5. Screw piston to rod making sure of a good fit, then back the piston off about 3/4 of the way. 6. Apply (high strength) grade 680 Loctite® to rod thread and into piston thread on top of rod. Screw the piston clockwise all the way down. 7. Use spanner wrench to torque down piston. 8. Prick punch rod with center punch (2 places) so rod thread protrudes into piston thread. Clean any loose material and Loctite®. 9. Install new seals on piston; lubricate with grease or equivalent. 10. Install piston into tube without damaging. NOTE: Allow Loctite® to cure for 3 hours before applying test pressure to assembled cylinder. 1. There will be a circular retainer or a square retainer at the rod end. If there is a circular retainer, remove the socket head cap screws. If it is a square retainer, remove the tie rod nuts. 2. Remove the circular retainer as shown in Fig. 2 3. Remove the rod cartridge by inserting a screwdriver in the external groove. Pry carefully. See Fig. 3 4. Clean cartridge recess in the head. 5. Lubricate new rod cartridge and seals with grease or equivalent inside and out before assembly. 6. (Caution) Place new cartridge on the rod end being sure to use a “screwing motion”. 7. Insert cartridge (now mounted on rod) into head recess. 8. Replace circular retainer plate, tie rod nuts or socket head cap screws and tighten to original torque specs. See Fig.1 for Torque Specs or see Fig 4 for tie rod nut tightening pattern. ROD CARTRIDGE REPLACEMENT FIG. 1 FIG. 4 12-7-16 RETAINER RING SCREW TORQUE SCREW SIZE TORQUE FT/LBS. 1/4-20 15 5/16-18 32 3/8-16 60 1/2-13 110 5/8-11 220 FIG. 2 FIG. 3