00591-53443-81

Frequently Asked Questions

Q: Does part 00591-53443-81 fit INTERTHOR and Toyota branded manual pallet jacks?
A: Part 00591-53443-81 is an INTERTHOR seal kit designed for Toyota manual pallet jack hydraulic pumps. This kit is compatible with both INTERTHOR and Toyota branded manual pallet trucks using matching hydraulic pump designs. Verify your hydraulic pump model matches before ordering.

Q: What is the maximum system pressure this seal kit supports?
A: Part 00591-53443-81 is rated for a maximum system pressure of 3000 PSI. This rating applies to the composite nitrile and glass-filled nylon seal components. Systems operated above this pressure risk seal failure and hydraulic fluid leakage.

Q: What are the material specifications for this seal kit?
A: Part 00591-53443-81 is constructed from nitrile (Buna-N) elastomer at 70 Shore A nominal hardness, combined with glass-filled nylon backing rings. This composite construction provides superior durability in high-pressure pump applications, enhanced resistance to thermal cycling, and extended seal life compared to single-material designs.

Q: What hydraulic fluids are compatible with this seal kit?
A: Part 00591-53443-81 is compatible with standard ISO 6743 mineral-based hydraulic oils. Nitrile elastomer seals resist common mineral hydraulic fluids, water glycol fluids, and synthetic PAO oils. Verify your system fluid type is compatible before installation.

Q: When should this pump seal kit be replaced?
A: Replace part 00591-53443-81 when pump strokes become weak or incomplete, hydraulic fluid leaks from the pump area, the pump makes grinding or unusual noises, or fluid appears foamy or discolored. Seal degradation typically occurs after 3000 to 8000 pump cycles depending on operating conditions and maintenance.