Terex Genie GR-26J Service Manual

Also see for Genie GR-20J: Service manual Operator's manual

Section 4 • Repair Procedures4 - 34 GR™-20J • GR™-26J Part No. 227656GTMarch 2022FUNCTION MANIFOLDHow to Adjust the Platform LiftRelief ValveNote: Be sure that the hydraulic oil level is at theFULL mark on the hydraulic tank.1 Block the wheels at the steer end of themachine.2 Using a suitable lifting device, place a660 lbs / 300 Kg test weight in the center of theplatform. Secure the weight to the platform.3 Locate the lift relief valve on the functionmanifold (schematic item G).4 Turn the key switch to ground control and pullout the red Emergency Stop button to the onposition at both the ground and platformcontrols.Note: Rotate the red Emergency Stop button atplatform control one quarter turn in a clockwisedirection to restore the power supply. The redEmergency Stop button returns automatically tothe out, or on position.5 Press and hold the function enable button.6 Press and hold the lift function button and raisethe platform approximately 12 inches / 30 cm.Result: The platform should lift the weight.Proceed to step 12.Result: The platform does not lift the weight.Proceed to step 7.Component damage hazard. Donot continue to operate themachine if the hydraulic pump iscavitating.7 Turn the key switch to the off position.8 Hold the lift relief valve with a wrench andremove the cap (schematic item G).baa lift relief valveb system relief valve9 Adjust the internal hex socket. Turn it clockwiseto increase the pressure. Install the relief valvecap.10 Turn the key switch to ground control.11 Repeat the procedure beginning with step 5.12 Lower the platform to the stowed position.13 Turn the key switch to the off position.14 Adjust the internal hex socket. Turn itcounterclockwise to decrease the pressure justuntil the platform will not lift the weight. Installthe relief valve cap.15 Turn the key switch to the ground control.16 Activate the platform up function and attempt toraise the platform.Result: The platform does not lift the weight.Proceed to step 18.Result: The platform lifts the weight. Proceed tostep 12.17 Turn the key switch to the off position andremove the weight from the platform.