Remove/install fuel tank above rear axle

AR47.60-P-1000RFW

Remove/install fuel tank above rear axle

27.11.2019

Engine

780 in model 253.992/993

Modification notes

26.07.2019

Method description revised.

Operation step 1.

1

Electrical wiring harness

4

High-voltage lines

2

Reinforcement pipe, right

6

Fuel tank above rear axle

3

Reinforcement pipe, left

6

Fuel tank above rear axle

7

Lifting platform

8

Aggregate mount

9

Fuel tank protective frame

10

Tensioning straps

1.1

Electrical connectors

13

Bolts

16

Electrical connector

11

Coolant lines

14

Check straps

17

Bolts

12

Coolant hoses

15

Hydrogen filling line

 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

 Danger

Risk of explosion caused by escaping hydrogen or overheating of the fuel tanks when working on the hydrogen system. Risk of frostbite to body parts caused by escaping gas and by touching component parts carrying gas when emptying fuel tanks. Risk of asphyxiation caused by inhalation of air diluted by hydrogen. Risk of burn injuries by coming into contact with an invisible pale blue hydrogen flame.

AS00.00-Z-0030-01B

 Danger

Risk of death when working on component parts and systems with U >= 30 V alternating voltage (AC) or U >= 60 V direct voltage (DC)

Do not touch damaged or defective live component parts and lines or non-insulated electrical connections and lines.

AS00.00-Z-0035-01A

 Warning

Risk of injury to skin and eyes suffering scalding from contact with hot coolantspray. Risk of poisoning from swallowing coolant.

Do not open cooling system unless coolant temperature is below 90 °C. Open cap slowly and release the pressure. Do not pour coolant into beverage containers.
Wear protective gloves, protective clothing and safety glasses.

AS20.00-Z-0001-01A

Topical note

Notes on fuel cell system

AH00.00-P-0022-01RFW

Topical note

General information on handling vehicles with high-voltage on-board electrical system and/or lithium-ion battery and/or gaseous-fuel drive system

AH00.00-Z-0300-01A

Topical note

Notes on coolant

AH20.00-N-2080-01A

Topical note

Notes on battery

AH54.10-P-0001-01A

Notes on safety-relevant components

AH00.00-Z-0019-01A

 

Remove/install

1

Empty the fuel system with diagnostic device.

AR47.60-P-1006RFW

2

Ensure that the requirements for driving into the workshop are fulfilled.

Topical note

Requirements for driving into the workshop

AH00.00-P-0021-01RFW

3

Print out "tank system, fuel cell, form event log," fill out, and attach to the vehicle somewhere clearly visible.



OF00.00-P-3000-21RFW

4

Perform manual power disconnect of high-voltage on-board electrical system.

AR47.70-P-1010RFW

 diagnosis-based power disconnect is not possible in this case.

5

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

6

Remove underfloor panels.

AR61.30-P-1001RFW

 Installation: do not install the underfloor paneling until after the leak test.

7

Unclip electrical wiring harness (1) on right reinforcement pipe (2).

 Dismantling tool

*000589956300

8

Remove right reinforcement pipe (2) and left reinforcement pipe (3).

 Bolt, reinforcing tube to assembly frame for front fuel tank

*BA47.60-P-1002-01B

9

Remove high-pressure line from fuel tank above rear axle (6) to high-pressure fuel circuit gas distributor.

AR47.60-P-0035RFW

10

Remove the check valve.

AR47.25-P-0004RFW

11

Remove the rear part of the fuel cell exhaust air pipe.

AR49.10-P-0004RFW

12

Remove high-voltage lines (4) from the high-voltage distributor.

AR47.70-P-0004RFW

 Installation: Document, print out and sign the proper screw connection of all high-voltage direct screw connections during commissioning of the high-voltage on-board electrical system.

13

Remove the high-voltage lines (4) from the fuel tank protective frame above the rear axle.

AR47.70-P-0010-01RFW

 Nut, high voltage line cable duct to fuel tank protective frame above rear axle

*BA54.10-P-1023-02H

 Nut, high voltage line holder to fuel tank protective frame

*BA54.10-P-1022-02H

 Clip remover

*452589016300

14

Drain the low-temperature coolant circuit in order to remove the fuel tank above the rear axle.

AR20.20-P-7441-01RQ

AR20.00-P-1144-01RFW

 Record plug

*129589009100

 Clamp

*000589543700

15

Drain the high-voltage battery cooling system in order to remove the fuel tank above the rear axle.

AR20.20-P-7441-01RQ

AR08.50-P-0005-01RFW

 Record plug

*129589009100

 Clamp

*000589543700

16

Disconnect electrical connectors (1.1).

17

Unclip the electrical wiring harness (1) from the accessible area around the fuel tank protective frame (9).

 the electrical wiring harness (1) is secured to the fuel tank protective frame (9) with several line brackets.

 Dismantling tool

*000589956300

18

Remove coolant hoses (12) from the coolant lines (11).

 Hose clamp pliers

*454589003700

19

Unscrew screws (13) and place check straps (14) to one side.

 Bolt, assembly frame for rear fuel tank tensioning strap to body

*BA47.60-P-1004-01B

20

Position lifting platform (7) with aggregate mount (8) under the fuel tank above the rear axle (6).



000 588 03 62 00 Lifting platform

WS01.00-P-0091A

 Commercially available tool: universal aggregate mount

 secure the fuel tank protective frame (9) with tensioning straps (10).
The fuel tank protective frame (9) and the fuel tank above the rear axle (6) are firmly connected to each other.

 Bolt, assembly frame for rear fuel tank tensioning strap to body

*BA47.60-P-1004-01B

21

Remove screws (17).

 Bolt, assembly frame for rear fuel tank to body

*BA47.60-P-1003-01B

22

Carefully pull the hydrogen fill line (15) to the rear and carefully lower the lifting platform (7) until the electrical connector (16) is accessible.


Prevent the leverage effect of the hydrogen filling line (15) upwards.
Otherwise, the hydrogen filling line (15) will be damaged.

23

Separate electrical connection (16).

24

Remove, thread out and tie up the remaining electrical wiring harness (1) on the fuel tank protective frame (9).

 the electrical wiring harness (1) is secured to the fuel tank protective frame (9) with several line brackets.

 Dismantling tool

*000589956300

25

Carefully pull the hydrogen fill line (15) to the rear and carefully lower the lifting platform (7); extend the fuel tank above the rear axle (6) together with fuel tank protective frame (9).



000 588 03 62 00 Lifting platform

WS01.00-P-0091A


Prevent the leverage effect of the hydrogen filling line (15) upwards.
Otherwise, the hydrogen filling line (15) will be damaged.

 Aid of helper required.
During discharge, pay attention to the clearance.

26

Remove the fuel tank protective frame (9) from the fuel tank above the rear axle (6).

When replacing the fuel tank above the rear axle (6).

AR47.60-P-1005RFW

27

Print out the "Information about the fuel tank" form, fill it out, and attach it permanently to the relevant fuel tank.

When replacing the fuel tank above the rear axle (6).



OF47.60-P-3000-01RFW

28

Install in the reverse order.

29

Fill the low-temperature coolant circuit.

AR20.00-P-1144RFW

30

Fill the high-voltage battery cooling circuit.

AR08.50-P-0021RFW

31

Perform fuel system leak test.

AR47.60-P-0001RFW

 Tank system

Number

Designation

Engine 780 in model 253.992/993
with code ME02 (Fuel cell)

BA47.60-P-1002-01B

Bolt, reinforcing tube to assembly frame for front fuel tank

M12

Nm

106

 Tank system

Number

Designation

Engine 780 in model 253.992/993
with code ME02 (Fuel cell)

BA47.60-P-1003-01B

Bolt, assembly frame for rear fuel tank to body

M8

Nm

20

M10

Nm

53

 Tank system

Number

Designation

Engine 780 in model 253.992/993
with code ME02 (Fuel cell)

BA47.60-P-1004-01B

Bolt, assembly frame for rear fuel tank tensioning strap to body

M8

Nm

18

 High-voltage battery

Number

Designation

Model 253
with code ME02 (Fuel cell)

Model 253
with code ME05 (Hybrid drive 85 kW-94 kW variant (incl. plug-in))

BA54.10-P-1022-02H

Nut, high voltage line holder to fuel tank protective frame

Nm

8

-

 High-voltage battery

Number

Designation

Model 253
with code ME02 (Fuel cell)

Model 253
with code ME05 (Hybrid drive 85 kW-94 kW variant (incl. plug-in))

BA54.10-P-1023-02H

Nut, high voltage line cable duct to fuel tank protective frame above rear axle

Nm

8

-