Note: The high pressure fuel pump may only be removed and installed when the engine is cold. When installing the high pressure pump, make sure that no impurities enter the fuel system. Collect escaping fuel with a rag. The sealing ring and fitting must be replaced. High-pressure fuel lines must be screwed in without tension. The fuel in the power system is under pressure! Before opening the high pressure circuit of the injection system, the fuel pressure must be reduced to residual pressure.
Remove engine cover. Remove the air filter housing. Remove screw -1- and press air duct to the left.
Unscrew retaining clip -arrow-.
Unplug connector -2- from fuel pressure regulating valve -M276-. Remove fuel lines -3, 4 and 5-. Remove screws -arrows-. Carefully remove the high pressure pump. The roller follower may remain in the vacuum pump.
Installation
Replace high pressure pump o-ring. Before installation, check roller tappet for damage and replace if necessary. Insert the roller tappet into the vacuum pump (with anti-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 fitting must be replaced (from the high pressure zone). See High Pressure Pump Parts, -pos. 9-.
Rotate the crankshaft so that the roller tappet is in the lowest position. Replace the high pressure pump fitting. Insert the high pressure pump into the vacuum pump and fasten with screws. Tighten the screws by hand. Then tighten the screws crosswise to the correct torque. Insert both fuel lines and secure with spring clips. Tighten the union nut of the fuel pressure pipe by hand. Reconnect connector -2- to fuel pressure regulating valve -N276-.
Note: Check fuel system for leaks.