Other important factors are ensuring the hardness and roughness of the shaft are correct. A shaft hardness of HRC 45 is recommended for a rubber sealing lip, with a roughness of Ra 0.4-0.8. A higher shaft hardness of HRC 60 and shaft roughness of Ra 0.1-0.4 is recommended for a PTFE lip.
When it comes to choosing new spark plugs for your car, it is important to consider both cost and quality. While cheaper spark plugs may seem like a more cost-effective option upfront, they may end up costing you more in the long run if they need to be replaced more frequently. Investing in high-quality spark plugs made of premium materials can help improve your car's performance and fuel efficiency, ultimately saving you money in the long term.

rubber edge gasket.
Oil seals are used in many areas around the car.
Figure 6 shows the places where each seal type is used.
Finding oil spots under a parked vehicle can be both worrying and stressful for any vehicle owner. If the seal’s leak is small, oil may start to accumulate on the underside of the engine. But as the leak gets bigger, the oil leak will become visible in the front side of the engine.
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