BS4840E

SERVICE BULLETIN
REFERENCE:

Nova Bus Manuals

SECTION:

09: Engine cooling system

RS NO:

MQR 7621-1960

SUBJECT:

Charge air cooler (CAC) pipings

JUSTIFICATION:

Improved sealing of the joints of the charge air cooler piping.

LEVEL

1

APPLICATION DEADLINE: 2021SE01
CLAIM REFERENCE NUMBER: WB-4840

DIRECT CHARGES

DESCRIPTION

Replace the CAC clamps with the new constant-tension clamps.

2

–

TIME

LABOUR

MATERIAL

Nova Bus

Nova Bus

2h

–

–

–

MATERIAL
QTY

PART NO

REV.

DESCRIPTION

REPLACES PART N°

N99800

–

Constant-tension clamp

–

–

–

–

–

LEVEL 1

16
LEVEL 2

–

Materials will be available within 38 days once your order has been placed. To order, please
contact Prevost Parts by phone at 1‑800‑771‑6682, by fax at 1‑888‑668‑2555 or by email at
prevostparts.commandes@volvo.com. Specify document number, quantity of parts required and shipping address.

DISPOSAL OF PARTS
REMOVED PARTS ARE:

DISCARDED
*

RETAINED

Yes

–

* Dispose of the unused parts and the defective parts in
accordance with local environmental standards in effect.

REVISION HISTORY
REV.

DATE

NR

2020JL02

APPROVED BY:

CHANGE DESCRIPTION

Initial release

Jean-Nicolas Fournier

NQF772001 VERSION 3

WRITTEN BY

André Pelletier

Digitally signed by Jean-Nicolas Fournier
DN: cn=Jean-Nicolas Fournier, o=Nova Bus, email=jeannicolas.fournier@volvo.com, c=CA
Date: 2020.07.02 09:43:17 -04'00'

PAGE 1 OF 5

SERVICE BULLETIN
CLIENT

ORDER

ROAD NUMBER

BS4840E

VIN (2NVY/4RKY...)

QTY

FROM

TO

FROM

TO

L82JXG9775225

L82J3G9775406

125

Chicago Transit Authority - CTA - Illinois

L943

8200

8324

Chicago Transit Authority - CTA - Illinois

LB58

8325

8349

L82J7J9776906

L82J8J9776946

25

Calgary Transit - Alberta

LB85

8355

8362

L82K9J9776916

L82K6J9776923

8

Calgary Transit - Alberta

LB91

8363

8394

L82K3K9777030

L82K1K9777074

32

PAGE 2 OF 5
NQF772001 VERSION 3

SERVICE BULLETIN

BS4840E

WARNING

FOLLOW YOUR INTERNAL SAFETY PROCEDURES.

WARNING

This vehicle contains an electrochemical power storage device and high-voltage cables that can cause
serious, even fatal, physical harm from electric shock or chemical burns. It is the customer’s responsibility
to read the manufacturer’s documentation and to be aware of the risks associated with the system. See your
manual section 10: BAE Hybrid Propulsion System. Failure to comply with these instructions and electrical
safety measures may result in injury or death, as well as severe damage to the vehicle.

WARNING

The starting circuit is cut when the mode start switch on the engine control unit is in the neutral position
(center). When servicing the engine compartment, flip the switch to this position to prevent accidental starting
of the engine compartment. It is also recommended to lock out the switches to prevent accidental starting.

PROCEDURE
1.1.

Park the vehicle on an even surface with the transmission on neutral.

1.2.

Apply the parking brake and set the master control switch to the stop position.

1.3.

Set the battery disconnect switch in the battery compartment to the off position.

PAGE 3 OF 5
NQF772001 VERSION 3

BS4840E

SERVICE BULLETIN
x2

x4

x2
x2

x2

x2

x2

Figure 1 - CAC pipes Clamp Locations
REMARQUE

•
•
•
•
•
•
•
•

Never use an impact wrench to tighten the clamps.
For the tightening process, the tightening torque (N•m) and speed (rpm) have to be controlled. Avoid
high-speed tooling. Increase of tightening speed may lead to seizing/jamming.
The constant torque hose clamp is designed to automatically adjust its diameter to compensate for the
normal expansion and contraction of hose and tubing during vehicle operations and shutdown.
If clamp is tightened above recommended tightening torque, this will not increase pull-off force and seal
ability of the clamp proportionally to the applied torque.
If the tightening torque is exceeded, there is the danger of permanent damage to the clamp or hose (e.g.
failure of the clamp at reassembly or leakage).
Strongly avoid in any case multiple retightening of the clamp (risk of hose damage).
Strongly avoid in any case overtightening in means of torque and speed (risk of permanent damage to
clamp and systems).
Strongly avoid in any case fully opening of the clamp and remounting of the band to the housing (if
opened, replacing of the clamp is recommended).

PAGE 4 OF 5
NQF772001 VERSION 3

SERVICE BULLETIN

BS4840E

1.4.

Remove a clamp.

1.5.

Clean the surface of the silicone hose where the new clamp will be installed.

1.6.

Apply a lubricant such as P-80, N74253, between the new clamp and the pipe. This will prevent the clamp
from gripping the hose when tightening and applying the torque properly.

1.7.

Orient the new clamp to facilitate maintenance and tighten it as close as possible to the raised bead. Apply
a torque of 13.5 ±2 N•m (10 ±1.5 lb-ft).

1.8.

Repeat for all clamps shown in Figure 1, for a total of 16 clamps.

1.9.

Start the vehicle and let it run at fast-idle for 15 minutes.

1.10.

Apply the tightening torque of 13.5 ±2 N•m (10 ±1.5 lb-ft) again.

1.11.

Install the removed parts to do the work.

1.12.

Set the battery disconnect switch to the on position.

1.13.

The vehicle can be returned to service.

PAGE 5 OF 5
NQF772001 VERSION 3