Removing and installing/replacing front high pressure pump (S55 engine)
Disconnect NEGATIVE BATTERY TERMINAL (risk of fire due to short circuit on dismantling).
Electric fuel pump starts up automatically when door is opened!
Carry out installation work on fuel system only with coolant temperature below 40°C.
Fuel can emerge spontaneously at high speed when the high pressure line is released!
Introduced contaminants can cause malfunctions in the system!
- Do not allow any dirt particles or foreign bodies to get into the system.
- Remove all traces of dirt before removing lines or separate components.
- Use only fluff-free cloths.
- Seal all fuel system openings with protective caps or plugs.
Cover alternator with suitable materials.
Failure to comply with this procedure may result in an alternator malfunction.
Necessary preliminary tasks:
- Remove BOTH PRESSURE LINES .
- Remove BOTH FEED LINES .
Recycling:
Fuel escapes when fuel lines are detached.
Catch and dispose of escaping fuel.
Observe country-specific waste disposal regulations.
Removal:
Unlock connector (1) and remove.
Undo screw (2) and remove front high pressure pump.
When removing the front high pressure pump, ensure that the pump tappet does not fall out.
Installation note:
Replace the sealing ring (1) of the high pressure pump and coat with engine oil.
Installation:
Lay depth gauge (1) flat on high pressure pump flange.
Turn engine at central bolt in direction of engine rotation until the depth gauge shows that the camshaft has reached the BDC position .
When installing the front high pressure pump, ensure that the pump tappet is installed.
Tighten down screws (2).
Tightening torque 13 53 1AZ .
Connect and lock connector (1) at front high pressure pump.
Connector (1) must snap audibly into place.
Required follow-up work:
- Install BOTH FEED LINES .
- Install BOTH PRESSURE LINES .
Assemble engine.
Check fuel system for tightness.
Check function of DME.