What is the working principle of engine valves?

1 Answers
Annie
07/30/25 10:32am
The working principle of engine valves is driven by the camshaft through tappets and push rods. Symptoms of engine valve leakage: Valve leakage leads to weak vehicle performance, excessively rich or lean air-fuel mixture, incomplete combustion of fuel in the combustion chamber, resulting in increased fuel consumption; Valve leakage can also cause slow acceleration. Engine valve leakage can make the engine difficult to start, reduce power, cause incomplete combustion, severe carbon buildup, and even lead to individual cylinders not working. Causes of engine valve leakage: Valve burning leads to decreased sealing between the valve and valve seat; Valve clearance adjusted too small, causing the valve to not close tightly; Carbon buildup on the conical surface of the valve and valve seat; Foreign objects stuck during valve installation causing poor sealing; Pitting, scratches, spots, burns, or dents on the valve working surface; Poor grinding of valve sealing rings during maintenance; Excessive runout of the valve and valve stem; Excessive coaxiality deviation between the valve guide hole and seat hole.
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