A failure of a component may cause the valve to fail to perform its function, which, in the case of a control valve, prevents the reverse flow. In extreme cases, the failure could cause the component(s) to be lost in line, causing the failure or failure of other valves or equipment in line.

Valves that come into contact with the top of a piston are due to the synchronisation of the wrong engine caused by the breaking of the synchronisation chain and the incorrect assembly of the new belts and chains.

Locked valves are usually caused by an accumulation of echorosion deposits on the valve stem. Since the mounting of the stem in the guide is so snug, it does not require much accumulation on the valve stem to interfere with the free movement of the valve inside the guide.

The pressure valve usually leaks when the valve is not well placed or when the seal is broken or damaged. Losses can also occur when the pressure valve works very close to the adjustment point.

There are really simple. Expansion valves work under high pressure and cycle by high and low temperatures and pressures. Mobile parts are highlighted by these factors. Contamination in the system can also cause defects.