Start the engine and check for oil leaks round the sump flange. Stop the engine and tighten the mountings.
No single physical property of rubbers is responsible for the successful performance of an oil seal or ‘O’ ring. The ultimate tensile strength, breaking elongation, modulus, shore hardness, creep and stress relaxation in tension and compression loads are all important physical properties that characterize a seal or ‘O’ ring. Compression strength and set together with stress relaxation or decay are important for effective sealing. The difference in these properties in a swollen seal is highly critical. An optimum swelling value in a fluid medium is a desirable feature. De-swelling decreases the seal pressure against the wall of the housing where the seal is fixed, leading to leakage. Over swelling minimizes the physical properties of the rubber. Seals made of polysulfide rubbers have extreme fuel resistance but undesirably high compression set. The effect of temperature on the seal is an important factor. Swelling under stress can increase at higher temperatures and a suitable compounding technique should be adopted to reduce this effect.
Seals perform much better and longer when they are continuously lubricated with an oil that has the correct viscosity for the application and that is compatible with the seal lip elastomer material. The consideration of seal incompatibility, particularly with certain additives and some synthetic lubricants, should not be ignored, but unfortunately very often is.
Figure 1: Types of sealing devices
If necessary, lever it gently with a broad screwdriver blade, but take care not to bend the flange or damage the head.

The cover is fixed by nuts or bolts on top, or by screws round the edge. Loosen them all and remove them with their washers. If there are several oil-sealing washers under each fixing, note their order.
Nitrile is the most widely used rubber (elastomer) and it’s recommended as the best for almost all standard applications. This is solely due to the fact that nitrile has some intrinsic properties, such as low cost and compatibility with most environments. Some of the general applications of nitrile are non-latex gloves, automotive transmission belts, footwear, gaskets, synthetic leather, hoses, o-rings, and oil seals.
Choosing Quality Auto Parts Oil Seals:

In conclusion, the spark plug ignition coil is a critical component in the operation of an internal combustion engine. It is responsible for generating the high voltage needed to create a spark for ignition, and a properly functioning ignition coil is essential for engine performance. Regular maintenance and timely replacement of the ignition coil are necessary to keep the engine running smoothly and efficiently.
The range of uses of peroxydically cross-linked EPDM includes in hot water and steam seals. EPDM is also very resistant to ageing and ozone. Compared with the usual types of synthesis natural rubber it has good resistance to cold temperatures. EPDM is not resistant to aliphatic or aromatic hydrocarbons or mineral oil products. Resistance to chemicals, and also to oxidising agents, is very good. Temperature range from -50 °C to +140 °C depending on type.
Special exceptions still apply within the Volkswagen group. With PTFE oil seals, an aluminium or plastic housing is used in many different engine series. The Top Dead Centre (TDC) signal is no longer measured at the flywheel, but directly using a sensor on the rear crankshaft flange and integrated sensor in the oil seal. Special procedures and tools must be used for the disassembly and assembly of these parts.
You have to consider the speed at which the shaft will be moving, the housing bore, and the runout. These are important to make sure that you choose an oil seal that will not be exposed to unconducive abrasions.

Lubricants applied between moving and stationary elements of mechanical equipment help to prevent damage. But when the equipment are under high pressure, the lubricants tend to escape, hence the need for oil seals to prevent the clashing of dry parts. Practically all mechanical equipment, including car engines, assembly machines, and PTFE machined parts use these oil seals to prevent harmful interaction that can result in damaged parts.