As > built configurations ENGINES 471.9 The engine OM 471 has a one > piece cylinder head. There are two intake valves and two exhaust valves for each cylinder in the cylinder head. The narrow engine design means that overall a symmetrical location of the valves can ensue. This symmetrical valve pattern is optimum for the combustion. Tightening procedure for cylinder head bolts 1 > 38 Cylinder head bolt (M15Ґ2) 40 Bolt (M10) 39 Bolt (M10) W01.30 > 1105 > 78 Cylinder head bolts In order to ensure that the correct bolts are used when installing the cylinder head, on each bolt head there is an embossing which provides information on the thread strength of the respective cylinder head bolt.
The cylinder head bolts have the M15 2 thread and therefore have the embossing "15". All the cylinder head bolts must be tightened in four stages as per a set tightening pattern. The tightening torques and the tightening angle can be obtained from the repair instructions. As the cylinder head bolts elongate due to assembly, the shank length for each bolt which has already been used once must be measured before it is reassembled. The relevant bolt must be replaced when the permissible shank length is exceeded. i The cylinder head bolts are no longer assembled when the valve assembly is mounted. The valve assembly must be removed before dismantling the cylinder head.
i Introduction of engine OM 471 and exhaust aftertreatment > 09/2011 > 13 – This printout will not be recorded by the update service. Status: 09 / 2011 – GF01.30>W>0800H Cylinder head, as>built configuration 1.7.11