Smear clean engine oil on the pulley sleeve and seal, then refit the pulley with the key and keyway aligned. Tighten the bolt to the correct torque (consult a service manual or a dealer if in doubt).
Oil Seal Materials

Fitting an oil seal

2. Oil seal structure and functions
Shaft Hardness
Oil seals are vital to the daily operation of most factories and a wide range of industrial and commercial equipment. They are available in imperial and metric dimensions for both single- and double-lip design. Motors, Mechanical Hydraulic systems, pistons, and pumps utilize oil seals to protect internal components. Depending on the application, there are various material, size, and configuration options to best fit your needs. Learn more about oil seals, their composition, and the wide range of advantages they offer for your equipment.
Oil seals can also be known as rotary shafts seals, shaft seals, lip seals, elastomeric seals, and more.

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