- Another benefit of twin spark plug technology is enhanced engine durability. With two spark plugs firing simultaneously, the workload is evenly distributed, reducing the wear and tear on individual components. This results in a longer lifespan for the engine and its components, ultimately saving the driver time and money on maintenance and repairs.
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.
- Radial lip seals are the most common type of oil seal used to prevent leakage of fluids such as oil or grease in rotating machinery. They consist of a metal outer casing with an elastomeric sealing lip that is pressed against the shaft to create a tight seal.
Air side face


Selecting Quality Gaskets
Viton®
High level of chemical resistance
High temperature resistance


A typical oil seal consists of three common parts: an outer ring, the sealing element, and a spring. The exterior metal ring component provides strength and rigidity to the oil seal in the bore or recessed groove. Attached to that ring is the sealing element. This flexible interior component of the oil seal, the O-ring, prevents any fluid leaks between the shaft and housing. A spring ensures the constant pressure that deforms the O-ring, creating a reliable seal while maintaining radial force on the shaft.
Figure 14.1. Shaft seals (DuPont Dow Elastomers).

PTFE oil seals
Choosing the correct oil seal application
With a helper holding the engine steady, remove the wedge supports, lower the engine and reconnect the mountings loosely.

