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Camshaft drive

Camshaft drive


Camshaft and tappets

The engine has a single overhead camshaft, which is driven via a chain drive system in which the fuel injection pump is also connected. The crankshaft drives the fuel injection pump via a duplex (double) chain system. The fuel injection pump also has a sprocket for a simplex (single) chain system. This simplex chain drives the camshaft.

The camshaft works via valve bridges, which means that the movement of each cam on the single shaft is transferred to two hydraulic tappets. In turn, these tappets work directly on the valves. The hydraulic tappets are automatically adjusted to the changes in the length of the valves at varying temperatures. They work in an oil bath and are supplied with oil via an oilway in the cylinder head. The biggest advantages are quiet running and very high reliability. The valves are manufactured of steel and have chrome plated stems. The exhaust valve discs are stellite faced.

Chain tensioners

Each of the chains is acted on by a separate chain tensioner, which is easily accessible for servicing. The tension is created by oil pressure.

Vacuum pump

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