Check exhaust gas recirculation cooler for leaktightness

AR14.20-W-7680MD

Check exhaust gas recirculation cooler for leaktightness

06.06.2018

Engine

936.9 in model 963, 964

Modification notes

03.05.2018

Pressure drop in exhaust gas recirculation cooler

BE14.20-N-1001-01A

07.05.2018

Work procedure completely revised.

1

Screw

4

EGR line downstream of exhaust gas recirculation cooler

Y621

Exhaust gas recirculation positioner

3

Latch

5

Seal

2

EGR line upstream of exhaust gas recirculation cooler

7

Exhaust gas recirculation cooler

6

Flange

8

Pressure pump

 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

 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

 Warning

Risk of injury caused by body parts being pinched or crushed as cab is tilted

Ensure that no one is within the tilting range of the cab as it is being tilted. Always tilt the cab all the way to the end position and secure with the safety strut.

AS60.80-Z-0001-01A

 Warning

Risk of injury. Skin or eye injuries may result when handling hot or glowing objects.

Wear protective gloves, protective clothing and safety glasses, if necessary.

AS00.00-Z-0002-01A

Topical note

Notes on self-locking nuts and bolts

AH00.00-N-0001-01A

Topical note

Notes on avoiding damage through contamination and foreign objects

AH00.00-N-5000-01H

Topical note

Notes on tilting the cab

AH60.80-N-0003-01A



Remove

1

Tilt cab.

2

Remove noise encapsulation.

3

Open cap at expansion reservoir.

4

Remove exhaust gas recirculation line upstream of exhaust gas recirculation cooler (2).

AR14.20-W-1061MD


Clean flange at exhaust gas recirculation cooler (7).
Leaks can otherwise occur when test tool is connected.

5

Remove screws (1) of exhaust gas recirculation positioner (Y621).



Check

6

Install fastener (3) between exhaust gas recirculation line downstream of exhaust gas recirculation cooler (4) and exhaust gas recirculation positioner (Y621).

 The seal (5) for the  latch (3) must point upwards.

 Bolt, exhaust gas recirculation line to exhaust gas recirculation positioner

*BA14.20-N-1003-01J

 Leak tester

*936589029100

7

Install flange (6) at exhaust gas recirculation cooler (7).

 Bolt, exhaust gas recirculation line clamp to exhaust gas recirculation cooler

*BA14.20-N-1001-01J

 Leak tester

*936589029100

8

Install pressure pump (8) at flange (6).

 Pressure pump

*124589242100

9

Apply compressed air to exhaust gas recirculation cooler (7) by means of pressure pump (8) and spray leak detection spray immediately afterwards on connecting points of test tools and separating points of exhaust gas recirculation lines.


Do not exceed test pressure.
Exhaust gas recirculation cooler (7) can otherwise be damaged.

 The connecting points must always be sprayed with leak detection spray immediately after being applied with compressed air, as this volatilizes very quickly.

Pressure drop in exhaust gas recirculation cooler

*BE14.20-N-1001-01A

10

Observe display on pressure pump (8).

 During the test, check whether leaks may exist at the parts previously sprayed with leak detection spray. If necessary, eliminate leaks via cleaning, reconnection or replacement of damaged parts.

Pressure drop in exhaust gas recirculation cooler

*BE14.20-N-1001-01A

If a pressure drop is discernible,



Check exhaust gas recirculation cooler (7), connection piece and exhaust gas recirculation line downstream of exhaust gas recirculation cooler (4) for damage, replace if necessary.

11

Remove fastener (3), flange (6) and pressure pump (8).



Install

12

Install exhaust gas recirculation line upstream of exhaust gas recirculation cooler (2)

AR14.20-W-1061MD

13

Replace sealing rings at exhaust gas recirculation positioner (Y621).

14

Attach exhaust gas recirculation line downstream of exhaust gas recirculation cooler (4) to exhaust gas recirculation positioner (Y621).

 Bolt, exhaust gas recirculation line to exhaust gas recirculation positioner

*BA14.20-N-1003-01J

15

Close cap at expansion reservoir.

16

Install soundproofing.

17

Perform engine test run, switch off engine and check for leaks in area of exhaust gas recirculation cooler (7).

 Visual inspection.

18

Tilt back cab.

Check values for exhaust gas recirculation cooler

Number

Designation

Engine 934.9, 936.9

BE14.20-N-1001-01A

Pressure drop in exhaust gas recirculation cooler

Test period

min

10

Test pressure

bar

2

Pressure drop

bar

0,1

 Exhaust gas recirculation

Number

Designation

Engine 936.9

BA14.20-N-1001-01J

Bolt, exhaust gas recirculation line clamp to exhaust gas recirculation cooler

M8

Nm

25

 Exhaust gas recirculation

Number

Designation

Engine 936.9

BA14.20-N-1003-01J

Bolt, exhaust gas recirculation line to exhaust gas recirculation positioner

M8

Nm

25