00591-04385-81

Frequently Asked Questions

Q: Is the 00591-04385-81 seal kit compatible with both Crown and Toyota manual pallet jacks?
A: The 00591-04385-81 is designed for manual pallet jack hydraulic pumps and cylinders. It fits Crown and Toyota OEM equipment that use this seal configuration. Cross-reference your jack model and hydraulic pump serial number with the specification sheet to confirm compatibility. Do not assume fit across all years and models of the same brand.

Q: What type of hydraulic fluid should be used with the 00591-04385-81 nitrile seals?
A: The nitrile elastomeric seals in this kit are compatible with ISO 46 and ISO 68 mineral-based hydraulic fluids commonly used in manual pallet jacks. Do not use synthetic or bio-based fluids unless the seal material certification explicitly approves them. Using incompatible fluid will cause seal degradation and hydraulic leaks within days of operation.

Q: How do I know when to replace the seals in the 00591-04385-81 kit?
A: Replace seals when you observe hydraulic fluid leaking from pump or cylinder rod areas, especially after load application. Sluggish or incomplete lift cycles also indicate seal wear. If fluid is contaminated with debris or discolored, replace the seals even if no visible leaks are present. Preventive replacement every 5 to 7 years of regular use is recommended for high-use equipment.

Q: What tools are needed to install the 00591-04385-81 seal kit?
A: Installation requires a hydraulic jack or press (to remove old seals without damage), seal kit tools or soft-faced mallets, metric socket sets, and a clean work area. Do not use screwdrivers or metal pry bars to remove seals, as they will damage grooves and cause new seals to fail. Allow 2 to 3 hours for a technician with pump and cylinder experience to complete the job.

Q: Will a leaking manual pallet jack still lift if I do not replace the 00591-04385-81 seals immediately?
A: A slowly leaking jack may still lift, but you will lose pressure during operation and the load may drift down unpredictably. Do not operate the equipment if seals are severely degraded, as the load can drop suddenly and create a safety hazard. Fluid loss also contaminates the remaining hydraulic fluid with debris. Replace seals as soon as leaks are confirmed to prevent equipment failure and injury risk.