Notes about Common-Rail components - AH07.16-P-0002-01SM

ENGINE 622, 651 in MODEL 447 

ENGINE 639.939 in MODEL 454.0 

ENGINE 642, 651 in MODEL 639 

ENGINE 642.896/898/992/993, 651.955/956/957 in MODEL 906 

ENGINE 651 in MODEL 636 

ENGINE 651 in MODEL 900 

ENGINE 660.940 in MODEL 450.3, 450.4 (except 450.418) 

ENGINE 660.950/951 in MODEL 451.3/4 

The following procedures and notes must be observed for removal/installation of common rail components:

• Carefully clean the working area on the engine and required tools before beginning removal of common rail components to ensure they are free of dirt and fluid.
• Ensure accessibility of the working area through removal of add-on engine components which may cause difficulty.
• Do not eat, drink or smoke.
• Only use tools to loosen and tighten fasteners and high-pressure lines. All other assembly or disassembly procedures must be performed by hand and without an aid.
• Close off opened connections using suitable caps.
• Keep container for assembly aid materials clean and seal or cover if not used.
• Install sealing rings while moist (use assembly oil or engine oil). For vacuum and water hoses, use assembly aid material Palatinol N or soap water; for leak oil line use assembly aid material Palatinol N or diesel fuel.
• Remove caps by hand and always immediately before assembly.
• Do not bend high-pressure lines and install unstressed.
• Observe assembly notes from manufacturer and specified tightening torques.
• Disassembly of common rail components is not permissible. In the event of failure, completely replace the respective common-rail components with the exception of the fuel distribution rail.
• When replacing common rail components, use the caps from the new part on the removed part as soon as the new part is built-in.
• Do not lay any objects on the common rail components; there is danger of unnoticed damage.
• After installing common rail components, all connections are to be checked for leaktightness and the leak oil line, if necessary by hand for tight seating.

When observing the detailed procedures, common rail components, apart from high-pressure lines on some engines, can be installed a number of times. Nevertheless, avoid unnecessary disassembly. Sealing rings and stretch bolts must always be replaced.

Before starting the engine after assembly operations on the fuel injection system or after driving until the fuel tank is empty, the following should be observed:

• Sufficient filling of fuel filter housing.
• Do not vent fuel injection system at high-pressure connections.
• If necessary, actuate the starter for a long time without a break.

For a running engine and within the first 30 s after switching off, no assembly operation should be conducted on the fuel injection system. There is a danger of fuel escaping under high pressure. The engine should be run for a few minutes at a medium rotational speed for the subsequent leak test and then switched off again. Then check the fuel injection system carefully for leaktightness (visual inspection). In the case of leaks despite a correct tightening torque, the common rail components involved should be replaced.