What is the waterproofing effect of rubber O-rings?

Waterproof effect of rubber O-ring
The waterproof ring of the cylinder liner is a rubber O-ring with a mostly circular cross-section. Compared with the skeleton oil seal, the structure is simple. It has no skeleton and no self-tightening spring. It is sealed by the rubber's own flexibility and elasticity. Improper installation will cause a large amount of cooling water in the water jacket to seep into the crankcase, resulting in deterioration of engine oil and poor lubrication quality, aggravating the wear of various moving parts of the engine, and even causing major failures such as burning bushes and holding shafts. The following should be noted:
(1) If the waterproof ring is too thin or the water seal groove of the cylinder liner is too deep, after the waterproof ring is installed in the water seal groove of the cylinder liner, it cannot rise above the arc surface by a certain height. At this time, you can add one at the bottom of the water seal groove Layer asbestos rope, coated with water-resistant calcium-based grease, and then put the waterproof ring into the water seal groove, and then press the cylinder sleeve into the body seat hole.
(2) If the waterproof ring is too thick or the water seal groove of the cylinder liner is too shallow, the arc surface is too much after installation. At this time, not only the installation of the cylinder liner is difficult, but also the rubber water seal or the cylinder liner can be squeezed. Abrasive cloth evenly polishes the rubber water seal until it fits into the water seal groove and has a proper height. Then apply grease to the surface of the rubber ring to press the cylinder liner into the body seat hole.
(3) If the thickness of the waterproof ring is uneven or the depth of the water seal groove is different, and the unevenness of the rubber ring protrudes after being installed on the cylinder liner, you should carefully check whether the problem is the rubber ring or the water seal groove, there will be The problematic parts are replaced.
 (4) Before the rubber waterproof ring is inserted into the water seal groove of the cylinder liner, the rubber ring and the water seal groove should be cleaned, and foreign substances should not be brought into the installation. After installing the rubber ring on the cylinder liner, you should carefully check whether there is any phenomenon such as twisting and grooving. Before installing the cylinder liner, you should carefully remove the dirt on the cylinder body and the lower bearing hole, and apply a layer of engine oil on the surface of the lower bearing hole, and then slowly press the cylinder sleeve into the bearing hole.