What is the composition of the valve train?
2 Answers
The valve train consists of the valve timing gear, camshaft and its components, rocker arm shaft and rocker arm assembly, valve pushrod, valve, cylinder head, valve seat, valve guide, valve spring, valve lock and its components, valve adjusting screw, and other parts. Below is a related introduction: Camshaft: It is the main component in the valve train, and its function is to control the opening and closing of the valves and the variation pattern of their lift. Overhead valve (OHV) engine: It also relies on the camshaft to drive devices such as the fuel pump, oil pump, and distributor. Tappet: Its function is to transmit the thrust force generated by the rotation of the camshaft to the pushrod (in OHV or mid-mounted camshaft engines) or directly to the valve (in overhead camshaft engines). Tappets are generally made of wear-resistant alloy steel or alloy cast iron. Pushrod: OHV engines have slender pushrods, whose function is to transmit the cam thrust force from the tappet to the rocker arm mechanism. Rocker arm: Its function is to change the direction of the force transmitted by the pushrod or camshaft and then transmit it to the valve to open it. The rocker arm assembly mainly consists of the rocker arm, rocker arm shaft, support seat, valve clearance adjusting screw, and other components.
From my experience, the valve train assembly mainly consists of the camshaft, valve pushrods or rocker arms, valve body and springs, sometimes including hydraulic lifters. The rotation of the camshaft drives the pushrods or rocker arms, transmitting power to open and close the valves for air intake and exhaust control, while the springs are responsible for returning the valves to their closed position. If issues occur in the valve train assembly, such as worn pushrods or weakened springs, the engine may experience increased noise, reduced power, and higher fuel consumption. For maintenance, I recommend regularly checking valve clearance and lubrication, promptly cleaning oil sludge to prevent sticking. While driving, pay attention to any abnormal engine noises as warning signs. Treating this system well ensures smooth engine breathing, extends its lifespan, and reduces the hassle of breakdowns. Safe driving relies on a healthy engine.
