Remove/install fuel pump

AR47.20-P-5710RF

Remove/install fuel pump

11.05.2020

Engine

177, 264, 274.9, 276.8, 642, 651.9, 654.9, 656 in model 253

Shown: rear compartment on the right with fuel tank maintenance access (for engine 651)

01

Claw wrench

1

Maintenance cover

2

Locking ring

2a

Cutout

2b

Catch tab

2c

Locking claw

3

Fuel line

4

Electrical connector

5

Fuel line

7

Transfer unit

7a

Molding

Pfeile

Recesses

6

Electrical connector

7

Transfer unit

M3

Fuel pump (FP)

 Danger

Risk of explosion caused by fuel igniting, risk of poisoning caused by inhaling and swallowing fuel as well as risk of injury to eyes and skin caused by contactwith fuel.

No fires, sparks, open flames or smoking. Pour fuels into suitable and appropriately marked containers only.
Wear protective clothing when handling fuel.

AS47.00-Z-0001-01A

 Caution

Risk of injury caused by scraping or cutting body parts on sharp vehicle parts

Always wear protective gloves when working on or near sharp and non-deburred vehicle parts.
Deburr repair panels.

AS00.00-Z-0017-01A

Topical note

Notes on avoiding damage through contamination and foreign objects

AH00.00-P-5000-01A

Topical note

Information on preventing damage to electronic components due to electrostatic discharge

AH54.00-P-0001-01A



Check

1

Check fuel level using vehicle diagnosis system.



AD00.00-P-2000-04B


 The fuel tank may be filled to at most 25% before the service opening on the fuel tank is opened.
The fuel will finds its way into the vehicle interior otherwise.

 If fuel tank is over 25% full,



empty the fuel tank.

AR47.10-P-4001RF



Remove

2

Open fuel filler flap and remove fuel filler cap.

3

Move front passenger seat to front-most position.

 Mark position of the front passenger seat.

4

Switch off ignition and store transmitter key outside of transmitter range (min. 2 m).

5

Remove seat cushion in rear passenger compartment.

AR91.12-P-1020LW

6

Remove maintenance cover (1).

AR47.10-P-4100-02LW

7.1

Release and disconnect electrical connector (4).

Engine 264, 274.9, 276.8, 642, 651.9, 654.9, 656 in model 253

7.2

Release and disconnect electrical connectors at transfer unit (7).

Engine 177 in model 253

8

Release, remove fuel line (5) and seal openings with suitable stop plugs.

Engine 642, 651.9, 654.9, 656 in model 253


Collect exuded fuel using an absorbent rag.
Soiling will occur in the vehicle interior otherwise.


Do not kink, crush or twist fuel line (5) and do not route in tight radii.
Otherwise the fuel line (5) can be damaged.

 Record plug

*129589009100

9

Release, remove fuel line (3) and seal openings with suitable stop plugs.


Collect exuded fuel using an absorbent rag.
Soiling will occur in the vehicle interior otherwise.


Do not kink, crush or twist fuel line (3) and do not route in tight radii.
Fuel line  (3) will otherwise be damaged.

 Record plug

*129589009100

10

Insert claw wrench (01) in cutouts (2a) at locking ring (2) , turn locking ring (2) counterclockwise.

 Claw-type wrench

*001589000700

11

Mark position of locking ring (2) relative to fuel tank.

12

Remove locking ring (2).

13

Lift transfer unit (7).


Lift transfer unit (7) only until electrical connection (6) can be disconnected.
If this is not observed, damage will occur to the electrical connection (6).


Collect exuding fuel with an absorbent rag.
Damage and soiling can occur in the vehicle interior otherwise.

14

Release and disconnect electrical connector (6).

 Engine 177, 264, 274.9, 276.8, 642, 651.9, 654.9, 656 in model 253
with code 916 (Fuel tank with large capacity - Volume 1)
There are two electrical connections (6).

15

Remove transfer unit (7) with fuel pump (M3).


Collect exuding fuel with an absorbent rag.
Soiling will occur in the vehicle interior otherwise.



Install

16

Clean contact surfaces of sealing ring at fuel tank and at transfer unit (7).

 Replace sealing ring.

Assembly cleaner

*BR00.45-Z-1028-04A

17

Position transfer unit (7) with fuel pump (M3) in swirl pot.


Collect exuded fuel using an absorbent rag.
Soiling will occur in the vehicle interior otherwise.

 Ensure correct seating of the fuel pump (M3) in the swirl pot.

18

Connect electrical connector (6) until it locks.

 Engine 177, 264, 274.9, 276.8, 642, 651.9, 654.9, 656 in model 253
with code 916 (Fuel tank with large capacity - Volume 1)
There are two electrical connections (6).

19

Position transfer unit (7) on fuel tank.

 The molding (7a) of the transfer unit (7) must point in the direction of travel.

20

Attach locking ring (2) in marked position and insert claw wrench (01) in cutouts (2a) at locking ring (2), tighten locking ring (2) in clockwise direction.

 Ensure the correct engagement of the catch tab (2b) between the recesses (arrows) on the locking claws (2c).

 Claw-type wrench

*001589000700

21

Remove stop plugs, attach fuel line (3) and lock.


Do not kink, crush, or twist the fuel line  (3), and do not route in tight radii.
Fuel line  (3) will otherwise be damaged.

 Record plug

*129589009100

22

Remove stop plugs, attach fuel line (5) and lock.

Engine 642, 651.9, 654.9, 656 in model 253


Do not kink, crush or twist fuel line (5) and do not route in tight radii.
Otherwise the fuel line (5) can be damaged.

 Record plug

*129589009100

23.1

Connect electrical connector (4) until it locks.

Engine 264, 274.9, 276.8, 642, 651.9, 654.9, 656 in model 253

23.2

Connect electrical connectors at transfer unit (7) until these lock.

Engine 177 in model 253

 Warning

Risk of accident from vehicle starting off by itself when engine running. Risk of injury (bruises and burns) resulting from working on the engine while it is being started or when it is running.

Secure vehicle to prevent it from starting off by itself. Wear closed and snug-fitting work clothes. Do not touch hot or rotating parts.

AS00.00-Z-0005-01A

24

Perform engine test run and check fuel system in area of fuel pump (M3) for leaks.

25

Fill extracted fuel.

For a tank capacity of more than 25 %.

AR47.10-P-4001RF

26

Attach fuel filler cap and close fuel filler flap.

27

Install maintenance cover (1).

AR47.10-P-4100-02LW

 Screw/bolt, maintenance cover to body

*BA47.10-P-1004-01P

28

Install seat cushion in rear.

AR91.12-P-1020LW

29

Bring front passenger seat into original position.

 Fuel tank

Number

Designation

Model 253

BA47.10-P-1004-01P

Screw/bolt, maintenance cover to body

Nm

3

Repair materials

Number

Designation

Order number

BR00.45-Z-1028-04A

Assembly cleaner

A 000 986 56 01