Can be replaced or corrected. Santana valve top is bent and can be calibrated and replaced. You can check the bending deformation of the valve stem. When the bending deformation exceeds the allowable limit, please correct or replace the valve. The bending compensation of the ejector pin needs to bend the arch upward, deform reversely with a press, and compensate the cold pressure on the press. The stamping amount is usually 10 times of the actual bending deformation and lasts for 2min. The bending deformation of tappet is expressed by straightness error, which should generally be controlled below 0.03 mm. The symptoms of valve damage are: 1, which affects the working efficiency of the engine and reduces the power of the car; 2. Make abnormal sounds. The idle speed of the engine is unstable during operation, or the acceleration becomes worse. Overtaking performance is also declining. In severe cases, the engine will be difficult to start and will not catch fire. Cars also leak air and deposit carbon. The valve is broken and the cylinder is unstable. Unstable cylinder will lead to engine jitter, engine power loss and exhaust pipe blockage. In severe cases, the tail gas will emit black smoke.