Special Bulletin

Revision: A

SP18-39A
Date

Expiration

Release

Page

11.2018

11.2020

1

1(37)

STEP 67 ADDED. A DATA RESET MUST BE PERFORMED

2018-12-10

SCR CONVERTER REPLACEMENT - AFTERTREATMENT SYSTEM

Prevost vehicles
B13R (9700 us/can)

DESCRIPTION
This special bulletin is the continuity of Special Bulletin SP18-35. Only if authorized, perform the
replacement of the SCR tank.

MODEL YEAR(S) AND VEHICLES INVOLVED
NOTICE TO SERVICE CENTERS
Verify vehicle eligibility by checking warranty bulletin status with SAP or via ONLINE WARRANTY
SYSTEM available on Service / Warranty tab of Prevost's website.

Specific GHG17 & OBD18 compliant vehicles
This bulletin does not necessarily apply to all the above-mentioned vehicles, some vehicles may have been modified
before delivery.

Writer: EL

Special Bulletin

SP18-39A
Date

Expiration

Release

Page

11.2018

11.2020

1

2(37)

MATERIAL NEEDED
Order kit SP18-39 which includes the following parts:
Part No.

Description

Qty

500952

SCREW, TAPPING BDG PH SS #8X1/2

12

504637

CABLE TIE, NYLON BLK

12

540067

EXHAUST CLAMP 5"

1

21021850

CLAMP, V-BAND 5-INCH

2

21095726

GASKET EXHAUST PIPE V-BAND JOINT, 5-INCH

2

22303390

NOx SENSOR, PRE

1

22303391

NOx SENSOR, POST

1

22998036

TIE, STAINLESS STEEL

4

23190006

SCR CONVERTER

1

NOTE
Material can be obtained through regular channels.

SPECIAL EQUIPMENT REQUIRED

Writer: EL

Special Bulletin

SP18-39A
Date

Expiration

Release

Page

11.2018

11.2020

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3(37)

Part 1- H3 SERIES AND X3 SERIES VEHICLES

Writer: EL

Special Bulletin

SP18-39A
Date

Expiration

Release

Page

11.2018

11.2020

1

4(37)

PROCEDURE

DANGER
Park vehicle safely, apply parking brake, stop the engine. Prior to working on the vehicle, set the ignition
switch to the OFF position and trip the main circuit breakers equipped with a trip button. On Commuter
type vehicles, set the battery master switch (master cut-out) to the OFF position.

PRELIMINARY STEPS
1. Open the engine compartment door and the SCR converter access door.
2. Remove the SCR converter access door. Doing so will
allow extraction of the SCR converter out of its
compartment.

3. The SCR converter is heavy, huge and the free space in the opening is limited. Do whatever is
necessary to protect the fiberglass and the paint around the opening giving access to the SCR. Using
adhesive tape, place pieces of cardboard around the area.
4. Remove the SCR overhead ventilation grille.

5. Loosen the clamp and then remove the diffuser
assembly with the drain tube attached.

Writer: EL

Special Bulletin

SP18-39A
Date

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Release

Page

11.2018

11.2020

1

5(37)

6. Support the exhaust pipe between the SCR and the
flexible section. Remove the insulating blanket around
the pipe and then remove the two V-band clamps
securing the exhaust pipe. Move the exhaust pipe to
clear it from the SCR converter compartment.

H3 SERIES

X3 SERIES

Writer: EL

Special Bulletin

SP18-39A
Date

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Release

Page

11.2018

11.2020

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6(37)

SCR CONVERTER REMOVAL
7. Disconnect the SCR converter drain tube

H3 SERIES

X3 SERIES

Writer: EL

Special Bulletin

SP18-39A
Date

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Page

11.2018

11.2020

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7(37)

8. Unscrew and remove the NOx sensor and module.
Return the NOx sensor with the defective SCR converter
to Prevost.

H3 SERIES

X3 SERIES

Writer: EL

Special Bulletin

SP18-39A
Date

Expiration

Release

Page

11.2018

11.2020

1

8(37)

9. Unscrew the PM (particulate matter) sensor from the
SCR converter.
10. Secure the PM sensor and harness next to the PM
sensor module on the panel.

Keep the PM sensor for reuse

H3 SERIES

PM SENSOR

X3 SERIES

11. H3 SERIES - Remove the module panel and put aside.

H3 SERIES
Writer: EL

Special Bulletin

SP18-39A
Date

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Release

Page

11.2018

11.2020

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12. X3 SERIES - Remove the module panel and put aside.

X3 SERIES

13. Install an appropriate lifting device to the lifting eyelets of
the SCR converter.

See the image on the right for an example of what should be
used ideally

14. With the lifting device, support the weight of the SCR
converter.

15. H3 SERIES - Remove the upper mounting bracket.
Unscrew and remove six bolts identified on the image.

H3 SERIES

Writer: EL

Special Bulletin

SP18-39A
Date

Expiration

Release

Page

11.2018

11.2020

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10(37)

16. X3 SERIES - Remove the upper mounting bracket.
Unscrew and remove seven bolts identified on the
image.

X3 SERIES

17. H3 SERIES - To give as much clearance as possible,
remove the insulating blanket pieces from the SCR
converter. This is necessary; otherwise, the SCR
converter will not pass through the opening.

H3 SERIES

18. H3 SERIES - Thread the upper bolt out about 1/4″.
19. H3 SERIES - Remove the lower bolt.

H3 SERIES - BOLTS SECURING THE SCR
CONVERTER TO THE CHASSIS - STREET SIDE

Writer: EL

Special Bulletin

SP18-39A
Date

Expiration

Release

Page

11.2018

11.2020

1

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20. H3 SERIES - Thread the upper bolt out about 1/4 in.
21. H3 SERIES - Remove the lower bolt.

H3 SERIES - BOLTS SECURING THE SCR
CONVERTER TO THE CHASSIS - CURB SIDE

22. H3 SERIES - Using the lifting device, lift the SCR converter a few inches so it will disengage

from the fixing points at the bottom.
23. X3 SERIES – Unbolt the lower support bracket from the
chassis (4 bolts).

X3 SERIES

Writer: EL

Special Bulletin

SP18-39A
Date

Expiration