HOSE AS 4824447 - Caterpillar

Illustration 1 g00314158
Valve System Components (1) Rocker arm (2) Bridge (3) Valve rotator (4) Valve spring (5) Pushrod (6) LifterThe valve system components control the flow of the inlet air and the exhaust gases during engine operation. Inlet valves allow inlet air to flow into the cylinders and exhaust valves allow exhaust gases to flow out of the cylinders.The crankshaft gear drives the camshaft gears through idlers. Both camshafts must be timed to the crankshaft in order to get the correct relation between the piston and the valve movement.The camshafts have three lobes for each cylinder. One lobe operates the bridge that moves the two inlet valves. One lobe operates the bridge that moves the two exhaust valves. The center lobe operates the fuel injector.As the camshaft turns, the lobes of the camshaft cause the lifters (6) to move up and down. This movement causes the pushrods (5) to move the rocker arms (1). The movement of the rocker arms causes the bridges (2) to move up and down on dowels in the cylinder head. The bridges open one rocker arm and simultaneously close two valves, or the bridges close one rocker arm and simultaneously open two valves. The valves can be either inlet valves or exhaust valves. There are two inlet valves and two exhaust valves for each cylinder.The valve rotators (3) cause the inlet valves and exhaust valves to turn while the engine is running. The rotation of the valves keeps the carbon deposits on the valves to a minimum. Minimizing the carbon deposits on the valves keeps the temperature of the valve face uniform. The uniform temperature of the valve face improves the service life of the valves.The valve springs (4) cause the valves to close when the lifters move down.