Note: The high-pressure fuel pump may only be removed and installed on a cold engine. When installing the high-pressure pump, ensure that no dirt gets into the fuel system. Collect any leaking fuel with a rag. The sealing ring and nipple must be replaced. High-pressure fuel lines must be tightened without stress. The fuel in the fuel system is under pressure! Before opening the high-pressure circuit of the injection system, the fuel pressure must be released to residual pressure.
Remove the engine casing. Remove the air filter housing. Unscrew screw "1" and push the air duct to the left.
Unscrew the fixing clamp "arrow".
Disconnect connector "2" from fuel pressure regulating valve "M276". Remove fuel lines -3, 4 and 5-. Unscrew the screws "arrows". Carefully remove the high-pressure pump. The roller tappet may remain in the vacuum pump.
Installation
Replace the sealing ring of the high-pressure pump. Before installation, check the roller tappet for damage, replace if necessary. Insert the roller tappet into the vacuum pump (taking into account the rotation lock).
Note: When installing the high-pressure pump, the roller tappet must be as cold as possible. When installing the same or a used high-pressure pump, the fuel pressure line nipple must be replaced (from the high pressure zone). See High Pressure Pump Parts and Assemblies, "item 9".
Turn the crankshaft until the roller tappet is at its lowest position. Replace the high-pressure pump nipple. Insert the high-pressure pump into the vacuum pump and secure with screws. Tighten the screws by hand. Then tighten the screws crosswise to the specified torque. Insert both fuel lines and secure with spring clamps. Tighten the union nut of the pressure fuel line by hand. Reconnect connector "2" to the fuel pressure regulating valve "N₂76".
Note: Check the fuel system for leaks.