Troubleshooting aging and deformation faults of high-temperature hydraulic pump shaft oil seals requires a systematic review of thermal conditions, shaft motion, lubrication, and material compatibility. When an oil seal fails in service, the visible symptoms often include leakage, lip hardening, deformation, cracking, uneven wear, or contamination around the shaft entry. These faults are commonly linked to excessive temperature, poor cooling, inadequate lubrication, shaft eccentricity, rough shaft finish, or the use of a material not suitable for the actual operating range. High temperature accelerates elastomer aging and weakens the lip’s ability to keep a stable contact line, making deformation more likely. Troubleshooting should therefore begin with checking working temperature, shaft speed, hydraulic media condition, and installation quality. It is also important to inspect spring integrity, housing fit, and possible contamination from dust or metal particles. Choosing industrial seals with better heat resistance and correct dimensional accuracy is often the most effective corrective measure. In hydraulic pumps used in industrial machinery, construction equipment, and heavy-duty systems, proper troubleshooting combined with reliable industrial seals helps reduce repeated failures, improve maintenance efficiency, and restore stable sealing performance under continuous high-temperature operation.