Remove/install low-temperature circuit valve

AR20.00-P-1048RFW

Remove/install low-temperature circuit valve

17.05.2019

Engine

780 in model 253.992/993

1

Fuel cell cover

2

Coolant hose

6

Screws

3

Coolant hose

7

Bracket

4

Coolant hose

Y85

Low-temperature coolant circuit 1 regulation valve 1

5

Electrical connector

 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

 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

 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 fuel cell system

AH00.00-P-0022-01RFW

Topical note

Information on preventing damage to electronic components due to electrostatic discharge

AH54.00-P-0001-01A

Topical note

Notes on coolant

AH20.00-N-2080-01A

 

Remove/install

1

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

Topical note

Requirements for driving into the workshop

AH00.00-P-0021-01RFW

2

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



OF00.00-P-3000-21RFW

3

Remove fuel cell cover (1).

4

Drain coolant from low-temperature circuit.

AR20.00-P-1144RFW

5

Pinch off coolant hoses (2, 3, 4) as close to low-temperature coolant circuit 1 regulation valve 1 (Y85) as possible.

 Clamp

*000589543700

6

Disconnect electrical connector (5).

7

Disconnect coolant hoses (2, 3, 4) from low-temperature coolant circuit 1 regulation valve 1 (Y85).

AR20.20-P-7441-01RQ

 Collect escaping coolant using a suitable clean container.

8

Remove screws (6) from bracket (7).

 Screw, switchover valve holder to supporting frame

*BA20.20-P-1002-02E

9

Remove low-temperature coolant circuit 1 regulation valve 1 (Y85) together with bracket (7).

10

Transfer bracket (7) of low-temperature coolant circuit 1 regulation valve 1 (Y85).

When replacing low-temperature coolant circuit 1 regulation valve 1 (Y85).

 Nut, switchover valve to holder

*BA20.20-P-1001-02E

11

Install in the reverse order.

 Engine radiator, coolant hoses and lines

Number

Designation

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

BA20.20-P-1001-02E

Nut, switchover valve to holder

M6

Nm

6

 Engine radiator, coolant hoses and lines

Number

Designation

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

BA20.20-P-1002-02E

Screw, switchover valve holder to supporting frame

M6

Nm

8