The car is made up of countless fasteners (bolts, nuts). Bolts and nuts are professionally produced by standard parts factories, and their "family" is very large. I know the fasteners, although I am superficial and respectful. In the era of Luban's first division, there should be no bolts and nuts. The woodworking tools he invented were all tightened with a tapered cone. There is no screw in the east and west towers of Quanzhou, Fujian. It depends on the vertebrae. The millennium does not fall, showing the wisdom of the ancestors. Teacher Hu Jianjun's discussion of the thread, my auto repairman is not taught. Today, we are really happy, the auto repair factory has to be flawed, the accessories are abundant, and the screws are piled up. However, my generation knows the ins and outs of the fastener family. In this regard, I read the "thread" article, read it with kindness, deeply cherish it, and work in the workshop for the long time, dealing with various thread "disability" experience. "Chai rice oil salt." First, the cylinder head bolts are one cylinder of the motorcycle. Of course, the four bolts are evenly distributed. The common four-cylinder engine cylinder head bolts are 10, and there are 2 adjacent cylinders, 16 cylinders, 20 cylinders and 20 cylinders. . Most of the threads are M1X1.5 or 1.75, and some models are M11X1.5 and M9X1.25 (Kia). Aluminum cylinder and cast iron cylinder (due to different materials), the hole depth, pitch and thread length of the thread are optional. The assembly of the cylinder head and the cylinder body, the maintenance manual has strict technical specifications. "The child does not teach, the father has passed", the book does not read, and he is wrong. Bolt locking torque can not be exceeded, super torque will inevitably lead to: 1 bolt is stretched (waist) scrapped, this kind of situation mostly occurs in M9 or M11 cylinder head bolts and young novices; 2 cylinder threads are uprooted, this pair of cylinders The body is a fatal injury, which must be re-tapping the screw hole of the cylinder screw hole. The cylinder screw holes are deep holes and blind holes. Limited by the thickness of the arm (waterway), it can be set up twice, and it must be successful every time. A Camry 2.4 engine was leaked into the factory for maintenance due to high temperature cylinder head leakage. The engine was removed and it was found that there were 4 loose sliding teeth on the 10 cylinder head bolts, which is equivalent to the collapse of the “half of the cylinder headâ€. It shows that the technology of the repair does not learn, does not enter the line, immoral and the driver's ignorance and adventure. I remember that if this happened in the 1950s, the Security Division would be open to the case. If this kind of case occurs in the braking or steering system, there will be a big event in human life. We should not forget the "Mitsubishi Pajero" incident. I still remember that when working at the Military 646 factory, a mechanic repaired the T34 tank engine and installed a cotter bolt to the military court. It is said that the exhaust manifold bolts are all the bolts (caps) of the whole vehicle. The fasteners of the exhaust manifold and the muffling exhaust duct are the most difficult to dismantle. It is rusted for a long time, often breaks, and it is difficult to advance and retreat. When disassembling, you must remember: "Do not fight unprepared." Before disassembling, spray the loose rust or old brake oil on the bolts (caps), keep the oil for 510 minutes, and make appropriate tapping vibration. It is also a good idea to lock the 0.10 mm and apply the rusting rust. Doing this “warm-up exercise†will bring convenience and success to the operation. Here is a Toyota RAV4, which is weak in power. After careful study of the malfunction, the third diagnosis is a three-way catalytic blockage. The "special" of the operation can enlighten us to have a clear-headed mind, and to give it a "special event" treatment for fasteners that have been subjected to long-term high temperature and rust, and it will do more with less. Let's say that the most difficult to remove the screws one Mercedes-Benz E220 mesh I" bridge shock absorber under the ball bracket fixed screw cone 10X1. Whenever the damper is replaced, this screw is the "blocker" hex wrench twisted, the screw is hexagonal slip Corner, "Huawei helpless bugs" Practice the truth, eat a meal, grow a wisdom. We started with the improvement tool and finally conquered it. The punch is modified with old tire bolts, no cost, good material and impact resistance. The hexagonal head is modified with an old sleeve joint. L Allen key, difficult to work. The disassembly procedure is shown in the figure: (1) using a small acetylene gun to locally heat the screw, soften the viscose; 2 loose rusting; 3 impact vibration; 4 disassembly, tube axial clearance to prevent hexagonal slippage. E diesel engine lubrication is more demanding than gasoline engine lubrication. Diesel combustion produces more fireworks than gasoline, especially on the piston and steel sleeve of the engine. The lubricating oil film is always affected by the carbon black generated during diesel combustion. Therefore, the diesel engine easily forms carbon deposits in the piston ring region. The sulfur content of the fuel, even for high-quality diesel, is 10 times higher than that of gasoline. For some residual diesel fuels, the sulfur content can be more than 100 times that of gasoline. The high sulfur content in the diesel fuel causes corrosion and wear of the piston ring and the cylinder liner, and the combustion products of sulfur can also accelerate the formation of deposits, requiring a higher base value of the oil to neutralize the acid formed after the combustion of sulfur. The diesel engine has a large load and a high compression ratio. For example, the main bearing pressure of gasoline engine is 5~8MPa, while the main bearing pressure of diesel engine is 10~12MPa. The cylinder compression of gasoline engine is relatively low, usually below 11, while the cylinder compression of diesel engine is relatively high, generally above 14. The content of additives in diesel engine oil is higher than that of gasoline engine oil. It must also be regarded as potential pollution. For example, the accumulation of deposits in the piston ring area will cause the snap ring, the accumulation of acid and the oxidation of oil will lead to the piston ring and cylinder liner. The severe wear and fuel consumption increase, which shortens the life of the diesel engine. This requires diesel oil to have good high temperature detergency, acid neutralization performance and thermal oxidation stability. (Continued from page 88) Diesel engine oil quality classification mainly includes the US API and the European ACEA two major systems. The US API classifies diesel engine oil into three categories: 1 medium-power diesel engine oil used in off-road, including CC, CD, and CF; 2 two-stroke high-power diesel engine oil, namely CD-n and CF-2; 3 US Series 8 Non-pressurized, low-pressurized or supercharged diesel engine oils operating under high-power, heavy-duty loads, such as CE, CF-4, CG-4, CH-4, and CI-4. (To be continued) E3 Warning: Are you Understand the basics of automotive engine lubricants, whether you have problems with engine oils at work, what are your insights on this basic knowledge, what do you think after reading this issue, lecture series Published in succession. We will set up relevant issues in each issue, no matter what basic knowledge you have, or want to express your own opinions, we warmly welcome your participation and look forward to your feedback. Beijing Automobile Maintenance and Maintenance Editorial Department Pneumatic Standing Desk,Hydraulic Lift Tables,Furniture Hydraulic Desk,Hydraulic Computer Desk Changzhou Offistyle Furniture Co., Ltd. , https://www.offistylefurniture.com
The car is made up of countless fasteners (bolts, nuts). Bolts and nuts are professionally produced by standard parts factories, and their "family" is very large. I know the fasteners, although I am superficial and respectful. At the time of Luban’s predecessor, there should be no bolts and nuts. The woodworking tools he invented were all adopted.