Causes and preventive measures of automobile oil leakage

In the use of automobiles, oil leakage failures often occur, which will directly affect the technical performance of the automobile, cause the waste of lubricating oil and fuel, consume power, affect the cleanliness of the car, and cause environmental pollution. Due to oil leakage and the reduction of lubricating oil inside the machine, the machine parts are poorly lubricated and insufficiently cooled, which will cause early damage to the machine parts and even leave hidden accidents.

1. The main causes of common vehicle oil leakage

1. Product (accessories) quality, material or workmanship is poor; there are problems with structural design.

2. Improper high-speed assembly, unclean mating surface, damaged gasket, displacement or failure to install in accordance with operating regulations.

3. Uneven tightening force of the tightening nut, breakage of the sliding wire or looseness and fall off, etc. cause work failure.

4. After long-term use, the sealing material wears out excessively, deteriorates due to aging, and becomes invalid due to deformation.

5. Too much lubricating oil is added, the oil level is too high, or the wrong oil is added.

6. ​​Parts (side covers, thin-walled parts) on the joint surface are flexed and deformed, and the shell is damaged, causing the lubricant to seep out.

7. After the vent plug and the one-way valve are blocked, due to the pressure difference between the inside and outside of the case, oil leakage will often occur at the weak seal.

2. Measures to prevent vehicle oil leakage

1. Pay attention to the role of cushioning. The gasket between the parts of the stationary part of the automobile (such as each joint end face, each end cover, shell, cover cushion, flat enamel cover, etc.) plays a role of leak-proof sealing. If the material, production quality and installation do not meet the technical specifications, the sealing and leak-proof function will not be achieved, and accidents may even occur. For example, the oil pan or valve cover is difficult to compact due to the large contact area, which causes oil leakage. When disassembling, pay attention to proper placement, check carefully, and assemble according to specifications.

2. All kinds of fastening nuts on the car must be tightened according to the specified torque. If the packing is too loose or not tight, the gasket will leak; if it is too tight, the metal around the screw hole will bulge or the thread will be slipped and cause oil leakage. In addition, if the oil drain plug of the oil pan is not tightened or loosened, it is easy to cause oil loss, and then the machine damage accident of “burning bushes and holding shafts” will occur.

3. Replace the failed oil seal in time. Many moving parts (such as oil seals and O-rings) on the car will be mis-installed, causing the journal and the oil seal cutting edge to be out of concentricity, swaying and throwing oil. Some oil seals will lose elasticity due to the aging of the rubber when they are used for a long time. Any leakage should be updated in time.

4. Long-term use of automobile parts will cause excessive wear (such as pistons and cylinders, etc.), which will cause high-pressure gas in the combustion chamber to escape into the crankcase and force the oil to leak. Therefore, when the exhaust gas at the fuel filler cap is serious, the worn parts should be repaired or replaced as soon as possible.

5. Avoid blockage of check valves and vent valves. This causes the temperature in the tank to rise, and the oil and gas fill the entire space and cannot be discharged out of the canal, which increases the pressure in the tank and increases the consumption of lubricating oil and shortens the replacement cycle. After the engine ventilation system is blocked, the movement resistance of the piston is increased and fuel consumption is increased. Due to the difference in air pressure between the inside and outside of the case, it often causes oil leakage at the weak seal. Therefore, the vehicle needs to be inspected, dredged, and cleaned regularly.

6. ​​Properly solve all kinds of oil pipe joint sealing. Vehicle union nuts are often disassembled and assembled, which are easy to slip and loosen; the accuracy of the two joints’ bell mouths is poor, and the center lines of the two cones do not overlap and the contact is poor; the tapers are different and do not match, which will cause oil leakage. . Replace the union nut, use the grinding method to solve the conical surface seal, and make the nut compact to solve the seal.

7. Avoid wheel hub slinging oil. Too much lubricating grease in the hub bearing and cavity, or improper oil packaging, poor quality and aging failure; excessive temperature of the hub caused by frequent braking; loose axle nuts, etc., will cause the hub to throw oil. Therefore, it is useful to use the “cavity lubrication method” to dredge the vent holes, strictly select high-quality accessories, and perform assembly and high-speed according to process specifications.

Three, the main points of vehicle maintenance

Assemble under extremely clean conditions, without bumps, scratches, burrs and other attachments on the working surface of the parts; strict operating procedures, seals should be installed correctly to prevent deformation in place; master the performance specifications and use requirements of seals , Replace the failed parts in time; for side cover thin-walled parts, cold sheet metal correction is used; for the easily worn shaft hole parts, metal spraying, welding repair, gluing, machining and other processes can be used to achieve the original factory size; Use sealant as much as possible. If necessary, paint can be substituted to achieve the desired sealing effect; the nut should be repaired or replaced with a new part if the screw is broken or loose, and screwed to the specified torque; the appearance quality of the rubber seal should be carefully checked before assembly; use Special tools are press-fitted to avoid knocking and deformation; add lubricating grease according to regulations, and regularly clean and dredge the vent and one-way valve. As long as the above points are achieved, the problem of vehicle oil leakage can be completely cured.

The automotive parts and parts machining, PTJ Shop offers the highest degree of OEM service with a basis of 10+ years experience serving the automotive industry. Our automotive precision shop and experts deliver confidence. We have perfected the art of producing large component volumes with complete JIT reliability, backed by the quality and long-term reliability our customers expect.