pallet jack not lifting
Manual hydraulic pallet trucks are indispensable equipment in warehousing and logistics. One of the most common malfunctions is that the pallet truck does not lift, but it can usually be resolved through systematic troubleshooting. This guide will guide you from simple to complex, step by step diagnose and solve problems, ensuring that your device quickly resumes working. For complex repairs, please feel free to contact ZZ Industrial's professional technical support or use our original accessories.
Quick check
Is the load overloaded? Check if the weight of the transported goods exceeds the rated load capacity of the pallet truck (usually indicated on the vehicle nameplate). Overloading will directly result in the inability to lift.
Is the pressure relief valve closed? Confirm that the "lower/release" valve on the control handle (usually a lever or rotary handle) has been fully reset to the "close/lift" position. This is the most common human operational negligence.
Are the wheels free? Check if the pallet truck is stuck by obstacles or if the wheels (especially the two load wheels) rotate smoothly.
Hydraulic pump unit inspection
Insufficient or improper hydraulic oil: Check the hydraulic oil level. If it is too low, the designated specialized hydraulic oil needs to be added (no other oil can be used as a substitute). ZZ Industrial provides high-quality specialized hydraulic oil.
Internal faults of hydraulic pump: worn pump core, damaged plunger, or stuck/failed internal valves (such as inlet and outlet valves). This requires replacing the hydraulic pump assembly or repair kit. We provide hydraulic pump units and repair kits that are fully compatible with the original vehicle.
Pump body or oil cylinder intake (with bubbles in the oil): repeatedly lift and lower the handle without load throughout the entire process to perform exhaust operation. If it is ineffective, it may be necessary to replenish hydraulic oil and exhaust.
Sealing system inspection
Wear/damage of the main cylinder seal: This is the main cause of "pressure relief" and weak lifting. Need to replace the main oil cylinder seal (maintenance kit). ZZ Industrial offers various models of wear-resistant seal kits.
Leakage at the oil connection: Check for any signs of oil leakage in the joints and oil pipes between the pump and the oil cylinder. If necessary, tighten or replace the sealing ring/oil pipe.
Mechanical component inspection
Bearing/roller damage: Check whether the bearing at the connection between the fork and the frame is rusted or broken. Damaged bearings can cause significant resistance to movement. The bearings need to be replaced.
Fork or frame deformation: Check if the vehicle body has been deformed due to collision, causing mechanical jamming. This usually requires professional calibration or replacement of components.
Linkage mechanism issue: Check if the lifting linkage is loose, detached, or broken.
Preventive maintenance:
Regularly check the hydraulic oil level and cleanliness.
Avoid overloading during use.
Keep the equipment clean, especially the piston rod of the oil cylinder, to prevent dust and impurities from damaging the seals.
When not in use for a long time, lower the fork to the lowest position and store it in a dry place.
The problem of "pallet trucks not lifting" mostly stems from the hydraulic system (oil, pump, seal). By following the steps in this guide, you can diagnose most faults. If you need high-quality manual pallet truck accessories such as hydraulic pumps, seals, bearings, wheels, handles, etc., please visit the ZZ Industrial official website or contact our sales team. We provide you with a full range of reliable solutions.
