The block is unlikely to distort except after severe overheating, but check anyway using a steel ruler or similar high-quality straight-edge.
Viton Oil Seals

What are Oil Seals and how should they be ordered?
Seals are classified by O.D. wall material, lip type, and whether they have a spring or not.
Major oil seals are specified in ISO 6194-1 and JIS B 2402-1.
Table 2 shows the common types of oil seals, while Table 3 shows the features of each type of oil seal.
Table 4 lists the JTEKT oil seal type codes and corresponding ISO and JIS standards.
Recognizing and avoiding common installation mistakes is key to the longevity and effectiveness of oil seals. Here are some frequent errors to watch for:
With the help of tips and information from our suppliers, our specialists will be happy to explain how to install oil seals. Please read the instructions carefully before installation.
Oil leak: the most frequent failure of the oil seal

car engine gasket.
Lubricant Amount - Seals will always perform best when lubricated, however in some machines there are more likely to be dry spells. For these cases, selecting a leather or PTFE seal will be beneficial, as both can operate with less lubrication than others.
Leather Oil Seals - Leather Seals, also known as Type L Oil Seals, are most common in components that are subject to dirt and poor lubrication. Since they come pre-lubricated and are able to absorb fluids, leather oil seals are able to provide sealing properties in conditions that synthetic rubber is unable to.
Oil seals for cars
The dimensions of the 25x47x7 oil seal refer to its inner diameter, outer diameter, and thickness, respectively. These measurements are important in ensuring a proper fit for the seal in the machine or engine it is intended for. By providing a secure seal between moving parts, the oil seal helps to maintain proper lubrication in the machine and prevent the loss of oil.


Of course, all rubber materials and seals will provide a range of benefits; however, you will need to consider chemical compatibility, sufficient temperature ranges, pressure ranges, and more.
Oil gasket seals are used in various parts of the engine, including the valve cover, cylinder head, and oil filter housing. These seals are designed to prevent oil leaks and maintain the integrity of the engine components. The oil gasket seal ensures that the engine remains properly lubricated and free from oil leaks, contributing to its overall efficiency and reliability.