Chain Drive

Chain Drive







The camshafts are driven by a toothed chain, one for each cylinder bank. The oil pump is driven by a separate roller chain.

Toothed Chain




The camshafts are driven by the crankshaft using newly developed maintenance free toothed chains.

The toothed chain gear wheels are located on the crankshaft and on the VANOS unit. Use of the new toothed chains (1) optimizes the drive chain rolling process and reduces noise.

Crankshaft Sprocket




The crankshaft sprocket (3) has three sets of gear teeth:

1. One roller chain gear wheel for the oil pump drive.
2. Two toothed chain gear wheels for the camshaft drives.


NOTE: The sprocket will also be fitted to a 12-cylinder engine variant which will be available in the future. Please observe the installation instructions and the relevant labels (V8 Front/V12 Front) when installing the sprocket.


Chain Tensioner (cylinder bank 1-4)




A chain tensioner is mounted in the side of the cylinder head for each camshaft drive chain. There is a guide ball in the chain tensioner tip that moves in an arched groove in the tensioning rail

The tensioner seal must be replaced each time the tensioner is disassembled. The tensioners are the same for both the left and the right cylinder heads,

Tensioning Rail Bearing Pin




The bearing pin for the cylinder bank 1-4 drive chain tensioning rail is hollowed. There is a ball (check) valve in the bearing pin. The valve opens at an oil pressure of 1 bar and allows engine oil to flow to the tensioning rail via a port (1).

Chain Tensioner (cylinder bank 5-8)




An oil jet has been fitted to lubricate the cylinder bank 5-8 drive chain. There is a valve in the oil jet which opens at a pressure of 1 bar and supplies the drive chain with engine oil.


NOTE: Refer to the Repair Instructions when using the Special Tools shown below to adjust the camshaft timing.