

Refit the sump, taking great care not to disturb the gasket. Hold it up by hand and fit two front bolts and two rear ones to keep it in place while you refit the rest.
To act as a physical barrier retaining the lubricating oil where it is bound to be.
Iridium Spark Plugs for Car: Enhancing Performance and Efficiency
What are Oil Seals and the different types?
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Spring The spring supplements the tightening force (i.e., the lip radial load) to ensure enhanced sealing performance and tight contact between the shaft and the sealing edge.The spring also prevents the deterioration of main lip sealing performance caused by high heat or other such factors.
Almost every lip seal is constructed to have a flexible inner part that creates a dynamic seal on the moving shaft, as well as a hard outer casing that statically matches the machine-end cover. The flexible part is made from different grades of rubber, while the hard part is made of light-gauge metal or strong plastic.
Operating temperatures for engine oil seals (see Fig. 14.11 and cross-section of lip seal with garter spring in Fig. 14.22) vary widely, depending on engine design and location within the engine. Typically, the rear crankshaft seal is subjected to much higher temperatures than the front seal. Oil sump temperatures vary considerably, depending on provisions for oil cooling. This allows use of hydrogenated nitrile (HNBR), silicone, or acrylic elastomers for some seals in relatively low-temperature environments (120–140°C or 250–284°F). Standard fluoroelastomers (FKM), bisphenol-cured VDF/HFP/TFE terpolymers with 68–69% fluorine content, perform well in oil service up to about 160°C (320°F). More resistant fluoroelastomers are necessary for reliable long-term performance in more severe environments.
6, the seal is cheap.

oil seal 50 * 72 * 10.
Conventional oil seals are the traditional seals, which can be recognised by a spring on the inside. These oil seals are made of a metal housing that contains a rubber seal. This part is often made of elastomer and comes into contact with the surface of the rotating shaft.
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