- Fluoropolymer. FKMs, or Viton®, are perfect for high-temperature applications up to approximately 400° F. Additionally, they feature low compression characteristics. Seals of this material are highly resistant to solvents, gas, and petroleum or transmission oils, so they are a good fit for applications around these materials.
Please see the following for the types of sealing devices for bearings.
How to Select the Right Bearing (Part 7): Components surrounding the bearing
Choosing the correct type for your application
Double metal cased
Types of oil seals
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 .
Leather is probably the oldest of the lip materials still in common use, but the move towards mass production methods has seen a massive increase in the development of synthetic rubbers which lend themselves to accurate and repeatable injection and compression moulding. Nitrile (NBR) is still by far the most common elastomer for “normal” use, whilst Viton® (FKM/FPM) is rapidly replacing Polyacrylate (ACM) and Silicone (VMQ) for high-temperature applications. Viton® also has high resistance to abrasion and chemical attack making it a preferred elastomer. Recent developments in the use of PTFE for Rotary shaft seals has caused widespread interest particularly for high-speed shaft rotation or poor lubrication applications.