- Engine Performance Issues Any issues related to engine performance, such as misfiring or a rough idle, could relate to timing belt problems.
2. Tension Check Ensure that the belt has the correct tension. A belt that is too loose can slip, while one that is too tight can wear out faster and damage associated components.
- Oil seals, often made from high-quality rubber compounds or synthetic materials, are designed to prevent the leakage of lubricants while inhibiting the ingress of contaminants. The 8 in the name likely refers to the percentage of oil-resistant material used in the seal's construction, enhancing its ability to withstand exposure to various oils and lubricants without degradation.
0.1 to 0.32 μmRa and 0.8 to 2.5 μmRz
and the lead angle to no greater than 0.05°. (There is a risk that the lead marks will impede the sealing performance of the oil seal: see Figure 5.)
• Super helix seal (seal with one-way two-step screw)
How does an Oil Seal Work


Oil seals are commonly made from materials such as rubber, silicone, or polyurethane, with each material offering different properties and advantages. Rubber seals are flexible and cost-effective, making them suitable for a wide range of applications. Silicone seals offer high temperature resistance and chemical compatibility, while polyurethane seals are durable and abrasion-resistant.
Nitrile Oil Seals - Nitrile oil seals, which is the commonly used term for acrylonitrile-butadiene rubber seals, is a very good general-purpose option due to the flexibility of use across a variety of components. The resistance is strong against fats, hot water, gasoline, mineral oils, grease and animal oils, making them the most often-used oil seals. They do not have a wide temperature range, making them a poor choice for machinery that can see extreme changes in temperature.
Choosing the right oil seal
The oil seals represent the most important type of dynamic sealing on rotating shafts. During the last years, we witnessed a great evolution in the technology, starting from their shape to the materials used nowadays.
For more detailed information, please see the following:
There is a British Standard laid down for the control of synthetic rubbers. BS 3574 (1989) helps to determine shelf life – for instance, Nitrile (NBR) and Polyacrylic (ACM) are Group ‘B’ rubbers and have a 7-year life, whilst Silicone (VMQ) and Fluoroelastomers (Viton®) are Group ‘C’ rubbers and have a 10-year shelf life. PTFE and Leather do not come into this category but like the others should be kept in the original packing for as long as possible away from direct light, dust, and humidity. Ozone, which can also be produced by battery-driven forklift trucks has a very bad effect on synthetic rubbers. Finally, protect the sealing lip – DO NOT hang the seals on nails, wire etc.
The oil seal should be tough enough to withstand the pressure and the vibrations caused by the shaft and bore. Check if the oil seal is strong enough to tolerate the pressure and vibration.
Auto Head Gasket: Importance in Engine Functionality
For more detailed information, please see the following: