Valve damage and causes

Is the valve closed normally? Possible causes include inappropriate valve clearance settings, or the fact that the seat insert or valve guide is not reworking the center. If the interval between the valve guides is too wide or too small, fatal results may result. In this article, I will outline the possible valve failure and its cause.

This value has closed normally. The combustion gases flow through the valve seat and heat the valve head. This causes the valve head to overheat and the seat part to burn.

Spring inserted correctly during installation. An inclined spring generates lateral bending moment on the valve stem (M)

The resulting alternating bending stress ultimately ruptures the valve stem surface and damages the valve guide.

After installing the tappet, the minimum waiting time (at least 30 minutes) required before starting the engine was not observed. As a result, the extra oil in the work area of ​​the tappet does not have enough time to escape.

The valve does not close properly, it overheats and burns at the seat part. Fatigue failure in the fillet area can also be caused by one side stress of the valve head.

Excessive valve guide clearance due to excessive wear of the valve guide and excessive reaming during maintenance

Inflow of hot gases can lead to a large amount of carbon deposits in the rod guide area. If the valve hardens and does not close properly, the seat may overheat (burn or spray passage).

Lack of stem lubrication, rigidity and seizure in the guide. Corresponding damage such as overheating of valve head and seat part may occur.

Reusing the worn valve opening can loosen the clamping system during operation. As a result, friction corrosion occurs in the valve stem, and the valve weakens at this part. It may cause vibration fatigue failure

One side wear occurs at the end of the rod and skirt. The lateral force on the valve stem due to application of eccentric force causes fatigue failure in the region of the clamping system

Significant increase in pressure and temperature load in the combustion chamber due to burning failure

The valve head can not withstand high thermal and mechanical load, it is bent inward. As a result, a so-called tulip is formed and the valve head region bursts.

If the valve spring of the engine is damaged or weakened, various running performance and performance problems may occur. If the valve spring is damaged, excessive valve noise may occur, compression may be impaired, or serious damage may occur inside the engine. Behavior after break gives the most serious damage to the engine. If the spring breaks, the valve may collapse enough to fall into the cylinder and the piston may hit the cylinder. In addition, the stem lock or retainer releases the valve and falls into the cylinder, seriously damaging the piston, cylinder head, and other nearby parts.

Damage due to overheating of the engine may be serious. Overheating can damage pistons, cylinders, bearings, valves, and many other important engine parts. Therefore, do not ignore the overheat warning signal; please stop your car when the engine may be running above normal temperature for the first signature!

Rheumatic heart disease is caused by myocardial injury caused by inflammation and scarring caused by heart valves and rheumatic fever. Rheumatic fever is usually caused by an abnormal reaction of the body against streptococcal infections starting from childhood sore throat or tonsillitis. People in low and middle income countries with cardiovascular disease and other non-communicable diseases have difficulty accessing effective and equitable medical services to meet their needs. As a result, many people in middle and low income countries are found in the process of illness, and usually die in young people with cardiovascular disease and other non-communicable diseases, in the most productive years.