Remove the distributor cap . Before removing the distributor (See Removing and refitting the distributor ), mark the position of the rotor arm so that you can refit it just as it was.

Seals, including oil seals, have undergone a great development in recent years and are totally unlike the original product. PTFE has taken over the oil seals market for modern engines mainly because traditional oil seals started causing more and more problems. Such as evaporation of chemical plasticisers from the elastomeric material, which eventually caused engine oil leakage. Now, the focus is more on durability and frequency of servicing.
Silicone
The mechanical seal is used in a pump, mixer and other mechanical engineering scenarios to contain the fluid within a vessel where a shaft rotates through a stationary (or rotating) housing.
Shaft Surface Finish
Slacken the alternator or dynamo adjuster and pivot bolts, push the unit inwards and ease off the drive belt. Remove the belt completely.

J: Additional code is added here as an identifier when two or more seals have exactly the same type codes and dimensional numbers.
How to Choose the Right Oil Seal for Your Industrial Application
ERIKS