1.0 Purpose: To identify requirements for the replacement of ISS seals, o-ring and installation of gland nut to rod. 2.0 Scope: This instruction applies to the ISS units manufactured at Lift Technologies Inc. 3.0 Responsibilities: Employees/suppliers that are required to replace seals in the gland nuts within the ISS must follow the steps outlined below. Procedure: ISS Front Frame removal Remove forks from the carriage per manufacturer s instructions Raise and block carriage on the mast at work level; position the ISS in the middle of its range of motion Remove the six grade 12.9 M10-1.5x20 lower carriage claw bolts (8mm allen wrench or socket) and put aside bolts, claws and shims (if used, please note their position) for reassembly. Lower carriage to ground level until it stops. Remove the front frame and backrest assembly by lifting it out and upwards away from the front of the mast channels. THIS STEP REQUIRES EITHER 2 PEOPLE OR THE USE OF AN OVERHEAD LIFT. Place the front frame/backrest assembly face down on pallet or blocks to prevent damage to its painted finish. Remove key from truck and lock out truck for the repair procedure Rev-0 Page 1 of 10
Removal of sideshift rods and seals Place clean rags on the lower bar directly underneath the two hydraulic fittings into the ISS cylinder assembly. Loosen both the left and right hydraulic fittings (1/2 to 1 full turn) to relieve the sealing of the hydraulic system and facilitate removal of the sideshift rods. Remove the 2 sideshift rods by grasping and pulling them straight out from their bores and gland nuts. These rods will be replaced as part of this procedure to ensure the best results. Rev-0 Page 2 of 10
Use a pick to remove the rod wiper (black rubber) and the energized poly pack seals (cream colored) from both sides of the ISS cylinder assembly. Clean and visually verify the cleanliness of the inside bore of the gland nut and make absolutely certain that the two grooves for the seals do not contain any foreign matter. Rev-0 Page 3 of 10
Installation of new seals into gland nuts Wet the main seal groove (farthest from the open end) within the gland nut with hydraulic fluid using a small brush to lubricate the seal groove. Inside of seal-towards centerline of truck outside of seal Install the seal into the second slot from the unthreaded side of the Cylinder Head with the groove in the seal facing the inside of the cylinder. Start one side of the seal into the groove as shown. U-cup Seal with o-ring facing towards cylinder Use one thumb to guide the seal into the groove and other to apply force. Roll the seal around the groove using both thumbs until the seal snaps into the Rev-0 Page 4 of 10
groove. Be sure that the o-ring in the seal does not come out of the seal groove during installation. The seal should be seated properly in the groove as shown below. Properly seated U Cup seal Visually and manually inspect the seal inside diameter to ensure seal has seated correctly in the groove without distortion. Wet the wiper seal groove with hydraulic fluid using a small brush to lubricate the wiper groove. Rev-0 Page 5 of 10
inside of wiper outside (note the lip) of wiper Install the wiper seal into the groove located just inside the gland nut assemblies. Squeeze and insert the wide edge of the seal into the groove and work the remaining seal into the groove with your fingers. Please ensure that the raised portion of the wiper is facing outward. Rev-0 Page 6 of 10
Properly seated wiper and seal Ensure the raised portion of the wiper is facing outward. Lightly lubricate the wiper with hydraulic oil. Rev-0 Page 7 of 10
Remove one of the replacement sideshift rods from its packaging materials, handling it very carefully to avoid picking up any dirt or marring its surface. Identify the tapered end with the cylinder rod groove this end will be inserted into the ISS cylinder assembly. Carefully clean any dust or dirt from the rod using a lint free cloth and lubricate the outside of the rod lightly but completely with hydraulic oil. Moving the edge that is outward from the centerline of the truck in a small circular manner will help to properly engage the sideshift rod into the wiper. Carefully insert the rod into the ISS cylinder gland nut through the wiper seal and further to engage the main (energized poly pack) seal. Install by pressing the rod into the cylinder in a slow and smooth manner; using a hammer or other abrupt motion will damage the seals. Slide cylinder rod within the gland nut to engage the wiper seal and protrude by approximately.5 past the gland nut face (opposite the threads). Verify that the wiper does not become inverted when inserting the sideshift rods. If any portion of the wiper is inverted, carefully slide the sideshift rods in an outward direction to restore the seal to a proper, non-inverted position. Rev-0 Page 8 of 10
installing sideshift rod sideshift rod re-installed properly Repeat the previous 3 steps for the other side. Tighten both the left and right hydraulic fittings to 21 ft-lbs. VERIFY PRESENCE OF WEAR PADS AND GREASE Upper fork b Lower fork bar face Verify top wear pads are installed correctly Fit frame and backrest assembly onto spine, slide frame from side to side to disperse grease. Clean excess grease from ends of spine bars. Apply Blue Locktite 243 to holes (6) located at rear of frame lower bar. Rev-0 Page 9 of 10
Install claws (2) to rear of frame lower bar use (6)10mm-1.5 x 20 hex socket head grade 12.9 bolts (do not force bolts, if difficulty is found engaging thread, remove bolt and re-tap thread using an M10 tap) finger install hex screw and secure using a 44 +/-5 ft-lb torque wrench. Wipe up any hydraulic fluid and/or grease paying special attention to thoroughly clean the ISS sideshift rods, wipers and gland nuts. Replace key in truck and remove any lock outs used at the start of the repair procedure Start the truck, lift the forks to clear the floor and cycle the sideshifter from left to right several times to purge any air from the hydraulic system. After all air has been purged, test for the smooth operation of the sideshifter. Rev-0 Page 10 of 10