The reason why the chain saw engine pull cylinder bites the chain saw engine pull cylinder
How to judge the maintenance of the chain saw
Chainsaw engine pulling cylinder The pulling cylinder in the chain saw cylinder is blocked, just check the chain saw piston, usually caused by the following reasons:
1, the top of the chain saw piston The serious carbon deposition around the ring is mainly caused by the use of bad oil, such as the use of diesel oil or inferior two-stroke oil.
2. The air filter of the chain saw on the exhaust side of the chain saw piston is unclean, and the garbage blocks the carburetor fuel device. The adjustment is too small or the oil in the fuel is added too little, so that the gas enters the cylinder The concentration is reduced, and the lubrication is insufficient due to air leakage of the paper pad insulator, etc., and the cylinder is easy to be pulled in the place where the high temperature is caused.
3, The lower side of the air inlet of the chain saw piston basically has water in the cylinder, such as the use in rainy and snowy days, etc., the water enters the cylinder from the chain saw air filter, thereby making the lubricating oil film Mixed with water, the lower side of the suction side of the chain saw piston lacks the lubricating oil film. After high-speed operation, the heating causes the cylinder to be pulled;
4. The air inlet side of the chain saw piston pulls the cylinder. Due to the garbage entering from the air filter;
Causes of chain saw engine pulling cylinder and investigation
There are many kinds of chain saw engine pulling cylinder The reason, first of all what is a pull cylinder? First of all, let’s talk about the chain saw engine. When the engine is working, the piston and the piston ring reciprocate at a high speed in the cylinder. Due to the huge expansion thrust generated by the combustion of the mixture, the piston and the piston ring are in close contact with the inner wall of the cylinder through the oil film formed by the oil. Under normal circumstances, due to the isolation and buffering effect of the oil film, the piston and the piston ring are not in direct contact with the cylinder. However, in some specific cases, the two will be in direct contact, causing sliding friction and generating a lot of heat. If the heat dissipation conditions are not effectively improved, the metal surface of the piston, the piston ring or the inner wall of the cylinder may be melted, so that the sliding friction surfaces are fused together, resulting in longitudinal stretch marks during the high-speed movement of the piston. In severe cases, the two lock up, resulting in Cylinder phenomenon. So, what are the reasons for the chain saw to pull the cylinder?
1. Insufficient running-in of the chain saw engine at the initial stage and the cylinder pulling caused by high-speed operation
For the chain saw that has just left the factory, you can use the naked eye to see the inner surface of the cylinder of the chain saw engine and the piston, The piston rings are all very smooth. If a magnifying glass is used, it is actually composed of many uneven protrusions. During the running-in period of the engine, the surface must be run-in, the protrusions must be cut off, the surface will be smooth and the force will be uniform, so that it does not slide when sliding. Interlocking with each other, the operation can be smooth. Therefore, the new engine must undergo a certain degree of running-in after assembly. Otherwise, the higher protrusions on the mating surface of the piston, the piston ring and the cylinder will bear the concentrated load, the pressure per unit area is very large, the temperature will rise after friction, the protrusions will soften and melt, and the cylinder will be pulled.
Second, the overheating of the chain saw piston can also cause the cylinder to pull.
When the piston is overheated, local abnormal expansion will occur. Due to the deformation of the piston, the groove of the piston ring is twisted into a wave shape, and the piston ring and the groove of the piston ring are engaged together for a short time or even a long time, which causes the piston ring to fail to work normally. At this time, the edge of the piston ring is in direct contact and friction with the inner wall of the cylinder at a very high unit area pressure, so that the piston ring not only loses the function of sealing the combustion gas, but also destroys the oil film on the inner wall of the cylinder, thereby causing the cylinder to pull. The main reasons for the overheating of the piston are: poor gasoline oil quality, resulting in abnormal combustion of the mixture and resulting in high temperature; poor fuel supply system, ignition setting or adjustment, resulting in abnormal combustion of the mixture and resulting in high temperature; poor design of the piston body or piston aluminum parts Poor density, overheating of the piston due to insufficient heat transfer from the piston to the cylinder.
