UENR0623-02 11 Engine Operation Fuel injection pump and fuel transfer pump Camshaft Lip type seals are used on both the front of the crankshaft and the rear of the crankshaft. The engine has a single camshaft. The camshaft is made of cast iron. The camshaft lobes are chill hardened. A timing ring is installed to the crankshaft. The timing ring is used by the ECM in order to measure the engine speed and the engine position. The camshaft is driven at the front end. As the camshaft turns, the camshaft lobes move the valve system components. The valve system components move the cylinder valves. A timing ring for the balancer can be installed to the crankshaft.
The timing ring for the balancer drives the balancer. The camshaft gear must be timed to the crankshaft gear. The relationship between the lobes and the camshaft gear causes the valves in each cylinder to open at the correct time. The relationship between the lobes and the camshaft gear also causes the valves in each cylinder to close at the correct time. Gears and Timing Gear Case Illustration 8 g02859276 Typical example The crankshaft oil seal is mounted in the cover of the timing case. The timing case is made of cast iron. The timing case cover is made from aluminum. The crankshaft gear (5) drives the camshaft gear (4) and an idler gear (6) for the engine oil pump.
The idler gear (6) for the engine oil pump drives the oil pump gear (7). The camshaft gear (4) drives the idler gear (2) and the accessory drive gear (3). The idler gear (2) drives the fuel injection pump gear (1). The timing gears are made of steel. The camshaft gear rotates at half the engine speed. The fuel injection pump gear rotates at one and a half times engine speed.