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Camshaft drive

Camshaft drive


Camshaft and valve tappets

The engine has a single overhead camshaft driven via a chain transmission to which the injection pump is also connected. The crankshaft drives the injection pump via a duplex (double) chain system. Apart from this sprocket, the injection pump shaft is fitted with a sprocket for a simplex (simple) chain system which drives the camshaft.

The camshaft operates via valve bridges, which means that the movement of each cam on the shaft is transferred to two hydraulic valve tappets which affect the valves. The hydraulic valve tappets are automatically adjusted depending on the changes in valve length at different temperatures. They are placed in an oil bath and are supplied with oil through a duct i the cylinder head. The biggest advantages include quiet operation and reliability. The valves are manufactured of steel with chrome-plated stems while the exhaust valve heads are stellite-plated.

Chain tensioner

Both chains are affected by individual tensioners which are easily accessible for servicing. The tension is created with oil pressure.

Vacuum pump

A mechanical vacuum pump is fitted on the cylinder head by the flywheel end. The pump is driven directly from the camshaft and is lubricated by the engine lubrication system.