First, remove the one-way circlip and clip. Move the small snap ring on the tensioning head into the groove below, put it on the vice and press it in slowly. When you hear the sound at the position of the small snap ring, loosen the vice, and the piston will not come and will not be pressed too tightly. It will crush you and you won't get out. Then put the clip and circlip back.

What is engine timing? Engine timing is an important guarantee for engine ignition time and operation. Ignition advance angle refers to the angle of crankshaft rotation during a period of time from ignition between spark plug electrodes to piston operation to top dead center. The following information is related: ignition is too late: if ignition is too late, the mixture will burn when the piston reaches the top dead center, that is, when the volume increases, it will burn, reducing the pressure in the cylinder and reducing the engine power. At the same time, the contact area between hot gas and cylinder wall will increase, which will lead to overheating of the engine and increase fuel consumption. If the ignition is too early, the combustion will be completely carried out in the compression process, and the pressure in the cylinder will rise sharply, reaching the maximum pressure before the piston reaches the top dead center, which will give the rising piston great resistance, which will not only reduce the engine power, increase fuel consumption, but also cause deflagration.