246319 Removing and installing high-pressure pump
WM 246319 Removing and installing high-pressure pump
Tools
Technical values
Preliminary work
Information
Before replacing the high-pressure pump if you suspect that it is faulty, check the performance of the fuel pumps in the tank. -> 200201 Checking fuel pressure (low pressure) on DFI engines Testing and Inspection or -> 206601 Checking fuel delivery rate (low pressure delivery rate) on DFI engines Testing and Inspection
1. Remove engine compartment cover at the plenum panel at the middle and left. -> 700219 Removing and installing front trim (engine compartment) - section on "Removing"
2. Pull out the fuses for the two fuel pumps. This prevents the fuel pumps from starting when a door is opened.
Information
Assembly overview
Assembly overview - fuel distributor, high-pressure pump and fuel injectors
Removing high-pressure pump
WARNING
Toxic substances
- Danger of poisoning or suffocation
-> Ventilate the work area well.
-> Never ingest or inhale.
-> Read specific information on the Hazard Sheet.
-> Wear personal protective gear.
WARNING
Highly inflammable or explosive materials
- Danger of fire or explosion
-> Avoid contact with hot parts or sources of ignition.
-> Use suction to remove ignitable vapours.
-> Attach warning sign in a clearly visible position.
NOTICE
Dirt on injection system components (intake manifold injection and direct fuel injection system)
- Material damage
- Rough-running engine
- Bad exhaust emissions
-> Thoroughly clean connection points and adjacent areas before loosening them. If the engine is very dirty, wash it before starting disassembly work.
-> Lay removed parts on a clean surface and cover them. Do not use fibre-shedding cloths.
-> Carefully cover components or seal them if repair work will not be carried out immediately. Place rubber caps on connections. Seal intake openings with film or adhesive tape.
-> Only install clean parts. Do not take spare parts out of the packaging until just before installation.
-> Never use compressed air when the system is open. Do not move the vehicle.
WARNING
Leaking fuel supply lines
- Emerging fuel
- Risk of fire
-> Perform leak test.
Information
- Do not bend high-pressure lines. Always remove the high-pressure distributor pipe and other fuel-supply components in the high-pressure area completely. Check that the connection points are not damaged and are perfectly clean and make sure there is no thread damage. Fit union nuts on all connection points by hand before screwing in screws or bolts. Remove dirt on the conical/ball joints. Check connection points for leaks following fitting.
Information
- Absorb any escaping fuel using a suitable binding material or a cloth.
- Cloths which have absorbed fuel must be disposed of according to the applicable national laws.
- The fuel system must be depressurised before starting work on it.
- Only work on the fuel system in well-ventilated rooms.
- Any seals which have been removed must always be replaced.
- Do not use any sealant containing silicone or silicone spray when the injection system is open. Traces of silicone drawn in by the engine are not combusted and damage the oxygen sensors.
1. Place a cloth under the high-pressure pump. This absorbs leaking fuel.
2. Pull off cable plug on the high-pressure sensor -arrow-. Use assembly tool T10118 to do this.
High-pressure line on high-pressure pump
Information
Always replace the fuel hose as it will be damaged by the corrugated connection piece during removal.
Information
Always replace the fuel hose as it will be damaged by the corrugated connection piece during removal.
3. Disconnect the fuel supply hose (not shown) and fuel low-pressure hose -A- at the spring band clamps and remove the fuel lines.
Fuel low-pressure lines
4. Release high-pressure line (fuel line) at the union nuts -2-. To do this, counter at the hexagon and remove the line.
High-pressure line on high-pressure pump
5. Unscrew the three screws for the high-pressure pump -1-. For the bottom screw, use a thin tool and very carefully press the coolant pipe down. -2-
Mount for high-pressure pump
Accessibility of threaded joint
6. Remove the high-pressure pump, turn it slightly and release the bottom cable plug for the flow control valve using assembly tool T10118 or by hand. -arrow-
Cable plug for flow control valve
7. Remove the high-pressure pump. => Removing high-pressure pump
Removing high-pressure pump
8. Remove the drive tappet -1- and check for signs of damage. The drive tappet has a twist lock on the side. -2-
Drive tappet
Installing high-pressure pump
WARNING
Toxic substances
- Danger of poisoning or suffocation
-> Ventilate the work area well.
-> Never ingest or inhale.
-> Read specific information on the Hazard Sheet.
-> Wear personal protective gear.
WARNING
Highly inflammable or explosive materials
- Danger of fire or explosion
-> Avoid contact with hot parts or sources of ignition.
-> Use suction to remove ignitable vapours.
-> Attach warning sign in a clearly visible position.
NOTICE
Dirt on injection system components (intake manifold injection and direct fuel injection system)
- Material damage
- Rough-running engine
- Bad exhaust emissions
-> Thoroughly clean connection points and adjacent areas before loosening them. If the engine is very dirty, wash it before starting disassembly work.
-> Lay removed parts on a clean surface and cover them. Do not use fibre-shedding cloths.
-> Carefully cover components or seal them if repair work will not be carried out immediately. Place rubber caps on connections. Seal intake openings with film or adhesive tape.
-> Only install clean parts. Do not take spare parts out of the packaging until just before installation.
-> Never use compressed air when the system is open. Do not move the vehicle.
WARNING
Leaking fuel supply lines
- Emerging fuel
- Risk of fire
-> Perform leak test.
Information
- Do not bend high-pressure lines. Always remove the high-pressure distributor pipe and other fuel-supply components in the high-pressure area completely. Check that the connection points are not damaged and are perfectly clean and make sure there is no thread damage. Fit union nuts on all connection points by hand before screwing in screws or bolts. Remove dirt on the conical/ball joints. Check connection points for leaks following fitting.
Information
- Absorb any escaping fuel using a suitable binding material or a cloth.
- Cloths which have absorbed fuel must be disposed of according to the applicable national laws.
- The fuel system must be depressurised before starting work on it.
- Only work on the fuel system in well-ventilated rooms.
- Any seals which have been removed must always be replaced.
- Do not use any sealant containing silicone or silicone spray when the injection system is open. Traces of silicone drawn in by the engine are not combusted and damage the oxygen sensors.
1. Check that the drive tappet -1- is installed correctly. The drive tappet has a twist lock on the side. -2-
Drive tappet
2. Check sealing ring of high-pressure pump for signs of damage and replace if necessary. Avoid shearing off the sealing ring during installation.
3. Place high-pressure pump in installation position => High-pressure pump. Then insert bottom left screw.
High-pressure pump
4. Connect the lower cable plug for the flow control valve. -arrow-
Cable plug for flow control valve
5. Insert the three screws for the high-pressure pump. For the bottom screw, use a thin tool and very carefully press the coolant pipe down -2-. Press the high-pressure pump against the resistance of the spring and screw in screws (twist crankshaft if necessary until the drive tappet is at its lowest point). Fit screws -1-. => Tightening torque: 10 Nm (7.5 ftlb.)
Mount for high-pressure pump
Accessibility of threaded joint
6. Tighten the high-pressure line -A- uniformly and counter the high-pressure line in -direction of arrow- at the same time. Once tightened, the high-pressure line -A- and low-pressure hose -B- must not be touching.
Tightening torque:=> Tightening torque: 28 Nm (21 ftlb.)
Tightening fuel high-pressure pipe
Information
Always replace the fuel hose as it will be damaged by the corrugated connection piece during removal.
Information
Always replace the fuel hose as it will be damaged by the corrugated connection piece during removal.
7. Fit the fuel supply hose (not shown) and fuel low-pressure hose -A- and secure with spring band clamps. Check installation position -arrows-.
Fuel low-pressure lines
8. Connect cable plug for the high-pressure sensor -arrow-.
High-pressure line on high-pressure pump
9. Inspect high-pressure system for leaks.
1. Fit engine compartment cover at the plenum panel at the middle and left. -> 700219 Removing and installing front trim (engine compartment) - section on "Installing"
2. Fit the fuses for the two fuel pumps.