1. Cause of failure
1) The side clearance and open-end clearance of the piston ring are too large, or the labyrinth route of the gas ring opening is shortened, or the sealing of the piston ring; after the surface is worn, its sealing performance becomes poor.
2) Excessive wear between the piston and the Pneumatic cylinder will increase the gap between the matching Pneumatic cylinder and the piston will swing in the Pneumatic cylinder, which will affect the good sealing of the piston ring and the Pneumatic cylinder.
3) Because the piston ring is stuck in the piston ring groove due to glue and carbon deposits, the elasticity of the ring cannot be exerted, and the head-sealing surface of the gas ring and the Pneumatic cylinder wall is lost.
Pneumatic cylinder strain. When the Pneumatic cylinder is pulled, the seal between the piston ring and the Pneumatic cylinder is broken, resulting in low Pneumatic cylinder pressure.
5) Mismatched piston is installed. For some engines, the depth of the pit on the top of the piston is different, and the wrong use will affect the Pneumatic cylinder pressure.
6) The Pneumatic cylinder gasket is damaged, the valve-seat ring is loose, the valve spring is broken or the spring is insufficient, the valve and the valve guide are not tightly sealed due to carbon deposits or too small clearance, which hinders the up and down movement of the valve;
7) The timing gear is installed incorrectly, the gear keyway is incorrect, the timing gear is damaged or worn too much, the wheel load on the camshaft timing gear and the wheel are loose, etc., resulting in incorrect gas distribution phase.
8) Unmatched Pneumatic cylinder heads are used. If there are Pneumatic cylinder heads, the combustion chamber volume may be different. If they are installed incorrectly, the Pneumatic cylinder pressure will be affected.
Improper adjustment of the clearance of the intake and exhaust valves, or: poor sealing with the valve seat, or improper operation when testing the Pneumatic cylinder pressure.
10) For an engine equipped with a decompression device, the clearance of the decompression device is improperly adjusted, so that the valve is not tightly closed
2. Troubleshooting
At present, there are many methods to detect the Pneumatic cylinder pressure with the Pneumatic cylinder pressure gauge. The Pneumatic cylinder pressure can be detected by measuring the current of the starter and the voltage of the starter; in addition, the method of measuring Pneumatic cylinder by Pneumatic cylinder with the compressed air of the hose can also be used.
Post time: Sep-22-2022