13 53 192 Removing and installing/replacing a pressure line (N55)
Special tools required:
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.
- High pressure lines may be rescrewed a maximum of 10 times.
Necessary preliminary tasks:
- Remove IGNITION COIL of corresponding cylinder.
- Ignition coils must not be fouled by fuel!
The resistance of the silicone material is reduced significantly by contact with fuel, which may cause the ignition coil to fail! It is therefore essential to protect the spark plug slot against ingress of fuel with a cloth!
- Before installing ignition coils, clean spark plug slots with compressed air.
- Make sure the spark plug slot is absolutely clean.
Recycling:
Fuel escapes when fuel lines are detached.
Catch and dispose of escaping fuel in a suitable container.
Observe country-specific waste disposal regulations.
Fuel can emerge spontaneously at high velocity from the fuel injectors!
To reduce the fuel pressure, place rag over fuel injector and carefully tap against the fuel injector with a spanner.
There is a risk of injury if the fuel pressure is not reduced!
Release the pressure line on the rail first. To reduce existing fuel pressure if necessary. Fuel must not get into the spark plug slot. Then disconnect the pressure line from the injector.
Unscrew nuts (2).
Disconnect pressure line (1).
Installation note:
Reinstall rubber mount (3).
Mark pressure lines.
Seal rail and injector with a matching plug (1) from special tool kit 1 32 1 270 .
Seal pressure line (1) with a matching plug from special tool kit 2 32 1 270 .
When reinstalling lines, lubricate the thread and bearing face of the ball with a little transmission oil or grease! When they are installed for the first time the nuts have a coating of lubricant (only effective once). Penetration of lubricant into the fuel-conducting area should be avoided.
To ensure distortion-free installation of the pressure line and to avoid damaging the thread, it must be possible for both nuts to be screwed on easily by hand!
If the ball bush is not in the center of the sealing cone of the rail and injector when the pressure line is attached, the pressure lines must be relieved of tension.
If pressure lines are tensioned, see further procedure in the section:
Relieving tension on pressure lines and fitting.
Adhere to tightening sequence:
Insert pressure line (1), install together with rubber mount (3) and fit nuts (2) hand-tight only.
- First tighten down nut (1) on injector.
- Then tighten down nut (2) on rail.
Tighten down nuts with special tool 3 13 0 160 .
Tightening torque 13 53 9AZ .
Relieving tension on pressure lines and fitting:
If the ball bush is not in the center of the sealing cone of the rail and injector when the pressure line is attached, the pressure lines must be relieved of tension. To relieve tension on the pressure line, the pressure line of the adjacent injector on the same hold-down device must also be released and the hold-down device must be released.
- Release union nuts (2) on injectors.
- Release union nuts (3) on rail.
- Release screws (1) on hold-down device.
- Fit pressure lines hand-tight.
- Tighten screws (1) on hold-down device
Tightening torque 13 53 6AZ .
- Tighten nuts (2) on injectors.
Tightening torque 13 53 9AZ .
- Tighten nuts (3) on rail.
Tightening torque 13 53 9AZ .
Assemble engine.
Check fuel system for tightness.
Check function of DME.