13 53 158 Removing and installing/replacing rail (N20, N26)

WARNING: Observe warning on cylinder head cover.
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.

IMPORTANT: Wear full face guard and protective gloves.
Fuel can emerge spontaneously at high speed when the high pressure line is released!

IMPORTANT: Adhere to conditions of absolute cleanliness when working on the high-pressure fuel system.

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.

IMPORTANT: When working on the oil, coolant or fuel circuit, you must protect the alternator against dirt contamination.
Cover alternator with suitable materials.
Failure to comply with this procedure may result in an alternator malfunction.

IMPORTANT: Ignition coils must not be contaminated by fuel.
The resistance of the silicone material is reduced significantly by contact with fuel, which may cause the ignition coil to fail!

Necessary preliminary tasks:

Remove IGNITION COILS .
Remove and renew the PRESSURE LINE between rail and high pressure pump.

Recycling:

Fuel escapes when fuel lines are detached.

Catch and dispose of escaping fuel.

Observe country-specific waste disposal regulations.

Unlock connector (1) and remove.

Unscrew nuts (2).

Release screws (3).

Remove rail (4).

Rail installation is described separately from removal.

Fig 1: Identifying Rail, Connector, Screws, And Nuts

Courtesy of BMW OF NORTH AMERICA, INC.

Installing the rail:

Note:

Reconnecting:

When reconnecting the fuel line, lubricate the outer thread. Penetration of lubricant into the fuel-conducting area should be avoided.

NOTE: To relax the fuel system the hold-down devices must be slackened at the injectors before the rail is installed.

Release screws (1) and (2) and slacken hold-down device (3).

Fig 2: Identifying Hold-Down Device And Screws

Courtesy of BMW OF NORTH AMERICA, INC.

Install (4) rail, manually tightening nuts (3) and bolts (2) only.

NOTE:

Rail must still be displaceable on cylinder head.
Nuts (2) must be able to be screwed on easily by hand.
Push on connector (1) for high pressure fuel sensor.

Fig 3: Identifying Rail, Connector, Screws, And Nuts

Courtesy of BMW OF NORTH AMERICA, INC.

Follow the correct screw connection sequence.

First tighten screw (1).
Tightening torque 13 53 5AZ .
Then tighten screw (2).
Tightening torque 13 53 5AZ .

Fig 4: Identifying Hold-Down Device And Screws
Courtesy of BMW OF NORTH AMERICA, INC.

Follow the correct screw connection sequence.
First tighten screws (3).
Tightening torque 13 53 4AZ .
Then tighten nuts (2) at the injectors.
Tightening torque 13 53 6AZ .

Fig 5: Identifying Rail, Connector, Screws, And Nuts
Courtesy of BMW OF NORTH AMERICA, INC.

Assemble engine.

Check fuel system for tightness.

Check function of DME.