Precautions for choosing accessories for auto repair

How can I buy qualified auto repair parts? We recommend that car owners generally check whether the assembly parts are missing, whether the rotating parts are flexible, whether the glued parts are loose, whether the protective surface is intact, whether the surface of the parts is rusted, whether the joints are flat, whether the geometric dimensions are deformed, and the trademark logo Is it complete?

　　 1. Is there any missing parts in the assembly parts?

　　The regular assembly parts must be complete and intact to ensure smooth assembly and normal operation. If the individual small parts on some assembly parts are missing, the assembly parts will not work or even be scrapped.

　　 2. Whether the rotating parts are flexible

　　 When purchasing a rotating part assembly such as an oil pump, turn the pump shaft by hand and feel flexible and free from jamming. When purchasing a rolling bearing, support the inner ring of the bearing with one hand and rotate the outer ring with the other hand. The outer ring should be fast and free Turn, and then gradually stop. If the rotating parts do not rotate well, it means that the inside is rusted or deformed, so don't buy it.

　　 3. Whether the glued parts are loose

　　 An accessory composed of two or more parts. The parts are press-fitted, glued or welded. No looseness is allowed between them. For example, the plunger of the oil pump and the adjusting arm are press-fitted. Combined; clutch driven wheel and steel plate are riveted, friction plate and steel plate are riveted or glued; paper filter element frame and filter paper are glued together; electrical equipment thread ends are welded of. If any looseness is found during purchase, it should be replaced.

　　4. Is the protective surface intact?

　　 Most parts are coated with a protective layer when they leave the factory. For example, piston pins and bearing bushes are protected with paraffin; the surfaces of piston rings and cylinder liners are coated with anti-rust oil and wrapped with wrapping paper; valves, pistons, etc. are soaked in anti-rust oil and packaged in plastic bags. If it is found that the sealing sleeve is damaged, the packing paper is lost, or the rust preventive oil or paraffin wax is lost during the purchase, it should be returned.

　　 5. Whether there is rust on the surface of the part

　　The surface of qualified parts has both a certain precision and a bright finish. The more important the parts, the higher the precision, and the stricter the rust and corrosion protection of the packaging. Pay attention to inspection when purchasing. If the parts are found to have rust spots, mildew spots, cracks, loss of elasticity, or obvious cutting tool lines on the surface of the journal, they should be replaced.

　　 VI. Whether the joint is flat

　　 During the transportation and storage of parts, due to vibration and bumps, burrs, indentations, breakages or cracks are often generated in the joints, which affect the use of parts. Pay attention to inspection when purchasing.

　　 Seven, whether the geometric size is deformed

　　 Some parts are prone to deformation due to improper manufacturing, transportation, and storage. When inspecting, you can roll the shaft part along the glass plate to see if there is light leakage at the joint between the part and the glass plate to judge whether it is bent; when choosing the clutch driven disc steel plate or friction plate, you can use the steel plate and friction plate. Hold the sheet in front of your eyes to observe whether it is warped; when purchasing an oil seal, the end face of the oil seal with a frame should be in a perfect circle, which can be fitted to the plate glass without bending; the outer edge of the non-frame oil seal should be straight and deformed by holding it with your hand , It should be able to return to its original state after letting go. When purchasing various types of gaskets, attention should also be paid to checking the geometric dimensions and shapes.

　　8. Is the trademark identification complete?

　　The outer packaging of the authentic product is of good quality, the handwriting on the box is clear, and the overprint color is bright. The packaging boxes and bags should be marked with the product name, specification model, quantity, registered trademark, factory name, address and telephone number, etc. Some manufacturers also put their own marks on the accessories. Some important components, such as generators, distributors, fuel injection pumps, etc., are also equipped with instruction manuals, certificates and inspectors' stamps to guide users in proper use and maintenance. When purchasing, you should carefully recognize it to prevent you from buying fake and shoddy products.