How to Determine Poor Valve Sealing?

1 Answers
DelDylan
07/25/25 12:37am
Methods to determine poor valve sealing include: 1. The oil seepage method—place the valve into the valve seat and pour gasoline on the top surface; if there is no leakage, it indicates good sealing. 2. The marking method—draw even lines on the working surface with a pen, then insert the valve into the valve seat and tap lightly; if any lines remain uncut, it indicates poor sealing. 3. The tapping method—lightly tap the valve on the valve seat several times and observe the working surface of the valve seat; if there is a bright and complete ring of light, it indicates the sealing meets the requirements. The function of the valve is to specifically input air into the engine and expel exhaust gases after combustion. Structurally, valves are divided into intake valves and exhaust valves. The intake valve's role is to draw air into the engine to mix with fuel for combustion, while the exhaust valve's role is to expel the combusted exhaust gases and dissipate heat.
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