The connecting rod of the petrol engine is broken or the cylinder is cracked simultaneously
The crankshaft and the connecting rod contact surface bite dead.
The surface on which the connecting rod contacts the crankshaft has a scratch mark.
Failure cause: no or lack of lubricating oil, resulting in high temperature melting and tension of contact surface (inner surface of connecting rod and even surface of crankshaft).
No lubricating oil (gasoline engine oil) was added, or lubricating oil was added but not put in place, or lubricating oil was added in place but the machine was used at a wrong Angle, resulting in that the oil splashing wheel could not touch the oil, leaving no lubricating oil or lack of lubricating oil on the contact surface of crankshaft and connecting rod, leading to no lubrication on the contact surface.
Second, there is no cooling.
Normally, if it is at the rated working speed, a few minutes will cause the crankshaft and connecting rod to bite dead, causing the connecting rod to break and crack the cylinder.
The same problem can occur with fake oil.
(1) all internal combustion engines, crankshaft and connecting rod bite dead (or cuffing) because of the lack of oil;
(2) sometimes the oil stored in the machine damaged by the user does not have any chip traces, indicating that there is no oil or oil less than the level of the oil spatter wheel can not reach during operation, or the machine memory oil is added after the accident.
The machine oil added after the event is not used for lubrication, so it is clear and free of abrasive dust (the oil is gray-black).
(3) there is another case where the oil is enough, but it is used on a slope greater than 25 degrees. If the oil spatter wheel cannot reach the oil due to the excessive tilt Angle, the above fault or other parts will be pulled (or locked) and wear will be accelerated.