- Oil seals play a vital role in the performance and longevity of motors. These mechanical components are designed to prevent oil leakage from the motor's internal parts, ensuring that the lubricant stays within the system where it is needed most. In this article, we will explore the importance of oil seals in motors and their impact on the overall efficiency and lifespan of these machines.
- The 40x52x7 oil seal finds extensive use in automotive, industrial, and hydraulic applications where the prevention of oil leakage and protection against dust or debris ingress is paramount
- Firstly, let's understand the percentages. In the context of oil seals, these figures often refer to the percentage of the seal's cross-sectional area that comes into contact with the shaft or bore it seals. A 55% oil seal, for instance, indicates that 55% of the seal's circumference is in contact with the sealing surface. This percentage influences the seal's ability to withstand pressure, resist wear, and maintain a tight barrier against oil leakage.
Width number
Oil seals with outer metal cases may include finishes or treatments applied to the outer edge to aid in rust protection, identification, and sealing of scratches or imperfections in the housing bore. Common finishes applied to the outside edge of metal O.D. oil seals include plain (a bonding agent of usually a yellowish-green color), a color-painted edge, and a grinded-polished edge.
MECHANICAL SEAL
The block is unlikely to distort except after severe overheating, but check anyway using a steel ruler or similar high-quality straight-edge.

front hub oil seal. It is important to use the correct seal for your vehicle make and model to ensure a proper fit and seal.
VMQ (silicone)



Thoroughly clean the area around the oil seal and check how it is fitted. If you cannot see the outer end of the seal, remove the timing-belt cover or chain cover (not the belt or chain) and possibly the water pump (See Replacing a water pump ) to reveal it. On an engine with a belt-driven overhead camshaft , remove the belt and its drive sprocket .
When the bore and shaft centers are misaligned, seal life will be shortened because the wear will be concentrated on one side of the sealing lip.
MH: O.D. wall is a rubber material
HM: O.D. wall is a metal case
MH(S)H: O.D. wall is metal with a reinforced inner metal case