1、 Ensure that the logo is complete. Authentic products have good external packaging quality, clear handwriting on the packaging box, registration and bright color. The product name, specification, model, quantity, registered trademark, factory name, factory address, telephone number, etc. shall be indicated on the packaging boxes and bags, and some enterprises shall mark the accessories by themselves. Some important parts, such as generator, distributor and fuel injection pump, are equipped with user manual, certificate and inspector seal to ensure correct use and maintenance of users. Be careful when buying. Don't buy fakes.
2、 Check whether the geometric dimensions of auto parts are deformed. Some parts are easily deformed due to improper manufacturing, transportation and storage. During inspection, the shaft part can be rolled around the glass plate to ensure that the light leakage and bending at the place where the part contacts the glass plate. When selecting the clutch drive plate steel or friction plate, hold the steel and friction plate in front of you to confirm whether there is warpage. When selecting the oil seal, the end face of the oil seal with the skeleton shall mesh with the flat glass and be a positive circle without bending. The outside of the oil rod without skeleton shall be neat, and the deformation shall be grasped by hand. After letting go, it can be restored to the original state. When purchasing various down jackets, you should also check the geometric size and shape.
Third, see whether the joint is flat. During the transportation and storage of parts, due to vibration and collision, burr, indentation, damage or crack often appear at the joint part, which affects the use of parts. Pay attention to inspection when purchasing.
Fourth, check whether the surface of the parts is rusty. The surface of qualified parts has a certain degree of accuracy and gloss. The more important the parts are, the higher the accuracy is, and the more strict the anti rust and anti-corrosion treatment of packaging is. When purchasing, if the parts are found to be rusty, moldy, rubber cracking, loss of elasticity or obvious turning pattern on the target surface, they should be checked and replaced.
Fifth, ensure that the protective surface is intact. Most parts are coated at the factory. Piston pin, bearing paraffin protection and other piston rings, cylinder liner surface antirust oil and packaging paper packaging; Valves, pistons and other anti rust oils are soaked and packed in plastic bags. At the time of purchase, if the sealed envelope is damaged or the wrapping paper is lost, or the antirust oil or paraffin is leaked, it will be replaced.
Sixth, check whether the bonding parts are loose. For auto parts composed of two or more parts, the parts are completed by extrusion, bonding or welding. The pump plunger and adjusting arm are not allowed to be loosened by extrusion joint. The clutch driven wheel and the steel plate are joined by rivets, and the friction plate and the steel plate are riveted or bonded. The framework of the paper filter element is bonded with the filter paper. The wire ends of electrical equipment are welded. If it is found loose during purchase, it should be replaced.
Seventh, ensure that the rotating parts of auto parts are flexible. When purchasing rotating parts such as oil pump, rotate the pump shaft by hand and feel agile and unobstructed. When selecting rolling bearings, one hand supports the inner ring of the bearing and the other hand rotates the outer ring. Therefore, the outer ring must be able to rotate quickly and freely and must stop gradually. If the rotating parts cannot rotate correctly, the internal rust will corrode or deform. Please do not buy. Eighth, the assembly parts are impeccable. Formal general assembly parts must be fully equipped to ensure smooth assembly and normal operation. If a single small part in some component parts leaks, the component parts may not work properly or be scrapped.