Speaking of automobile pistons, then we have to talk about the phenomenon of piston knocking. This is one of the common automobile failures. Do you know how to solve such failures?
Before solving the problem of piston knocking, we must first understand what is causing this phenomenon.

◆The gap between the piston and the cylinder wall is too large.

After running for a period of time, the piston skirt and cylinder will be severely worn, causing serious out-of-round and knocking the cylinder.

◆Individual connecting rods are deformed due to various reasons, causing the piston to wear out, the gap becomes larger and the cylinder is knocked. Piston knocking will cause excessive engine fuel consumption, engine oil leakage, high oil consumption, and poor economy. When the piston hits the cylinder severely, the piston will be broken and the cylinder will be damaged. As a result, the connecting rod will break and the cylinder block will be damaged.

After the engine has been running for a period of time, the cylinder piston is worn out. In addition to the poor lubrication, the matching gap between the piston and the cylinder increases due to wear, and a serious step appears slightly below the first gas ring, causing the piston to knock the cylinder. Make a strange noise.

It is convenient to solve the problem if you understand the reason:

◆If there is an obvious knocking sound when the engine temperature is normal, try to avoid high-speed operation and disassemble and repair it as soon as possible.

After removing the cylinder head and pulling out the piston, it is found that the cylinder is severely out of round, strained, or the gap between the piston and the cylinder is too large. Replace the cylinder liner, piston and piston ring.

◆If the connecting rod is found to be deformed, it should be replaced as much as possible.

After the engine is started, there is a knocking sound during low-temperature operation. When the temperature is normal, the sound disappears, so you can leave it alone.