BS5119E

BS5119E
SERVICE BULLETIN
REFERENCE:
Nova Bus Manuals
SECTION:
08: Braking system
RS NO:
MQR 7621-1987
APPLICATION DEADLINE: 2022DE31
CLAIM REFERENCE NUMBER: WB-5119
EFFECTIVE IN PROD.: LD08 (2021AU)
SUBJECT:
Braking system
JUSTIFICATION:
Brake chambers may fail and cause the drive axle brakes to overheat.
LEVEL
DIRECT CHARGES
DESCRIPTION
LABOUR
MATERIAL
TIME
1
Replace the brake chambers.
Nova Bus
Nova Bus
3h
2
Replace damaged parts.
Nova Bus
Client*
see table on page 8
* The cost of the material will be reimbursed when claiming for this service document.
MATERIAL
QTY
PART NO
REV.
DESCRIPTION
LEVEL 1
1
N104241
–
MGM brake chamber, left
1
N104243
–
MGM brake chamber, right
LEVEL 2 (only if required*)
4
N38045
–
ELBOW 90 ° MALE M22X1.5 FL45-8
2
N95702-06
B
Hose assembly (QR1-C to chambers) Parking brake for L958, L959, LA23, LB29,
LB59, LB99
2
N95702-13
–
Hose assembly (QR1-C to chambers) Parking brake for LA73, LA76, LB78, LC32
2
N95702-10
B
Hose assembly (R14 to chambers), Service brake
1
N8902138
–
Brake lining kit (1 per axle)
1
N8895746
–
R14 Relay Valve
2
N8907581
–
ABS modulator
1
N8908326
–
Caliper LS
1
N8908325
–
Caliper RS
1
N8900426
–
Caliper LS
1
N8900425
–
Caliper RS
2
N8911106
–
Brake disc
Materials will be available within 73 days once your order has been placed. To order, please contact Prevost Parts :
For CANADA 1-800-463-8876 or [email protected]
For USA 1-800-621-5519 or [email protected].
Specify document number, quantity of parts required and shipping address.
* The material identified in Level 2 is to be ordered only for vehicles that meet the criteria defined in Level 1.
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
2021JL20
APPROVED BY:
CHANGE DESCRIPTION
Initial release
Daniel Theriault
NQF772001 VERSION 3
WRITTEN BY
André Pelletier
Digitally signed by Daniel Theriault
Date: 2021.07.22 12:20:40 -04'00'
PAGE 1 OF 8
SERVICE BULLETIN
CLIENT
ORDER
ROAD NUMBER
BS5119E
VIN (2NVY/4RKY...)
QTY
FROM
TO
FROM
TO
L958
5439
5442
S92J9G9775533
S92J9G9775631
New York City Transit - New York
L959
5443
5443
S92J0H9776118
S92J0H9776118
1
New York City Transit - New York
LB59
5444
5484
S92J7H9776195
S92J6H9776379
41
New York City Transit - New York
LA23
5485
5530
S92J5J9776380
S92J6J9776517
46
New York City Transit - New York
LA73
8504
8507
L82J8J9776445
L82J8J9776476
4
New York City Transit - New York
LB29
5531
5566
S92J9J9776687
S92J6J9776873
36
New York City Transit - New York
LA76
8508
8633
L82J9J9776924
L82J8K9777144
125
New York City Transit - New York
LB99
5567
5602
S92J2J9776935
S92J5K9777000
36
New York City Transit - New York
LB78
8526
8526
L82J3K9776984
L82J3K9776984
1
New York City Transit - New York
LC32
8634
8754
L82JXK9777145
L82J5K9777277
121
New York City Transit - New York
4
PAGE 2 OF 8
NQF772001 VERSION 3
SERVICE BULLETIN
BS5119E
WARNING
Follow your internal safety procedures.
PROCEDURE
1.1.
Park the vehicle on an even surface with the transmission on neutral.
1.2.
Set the master control switch to the stop position.
1.3.
Disconnect the starting circuit on the control box at the rear of the vehicle and set the battery disconnect
switch in the battery compartment to the off position.
1.4.
Block the vehicle's wheels and release the parking brake
CAUTION
For information on hoisting and towing of the vehicle, see section 18: hoisting and towing in the Nova Bus
maintenance manual. Use appropriate hoisting equipment for your protection and to prevent damage to
the vehicle.
1.5.
Lift and secure the vehicle so that the wheels can be removed.
1.6.
Remove the vehicle drive axle wheels.
1.7.
Unscrew the release bolt until it comes out completely to ''cage'' the brake chambers.
Fully unscrew the release bolt
Figure 1 - Fully Unscrew the Release Bolt
PAGE 3 OF 8
NQF772001 VERSION 3
SERVICE BULLETIN
BS5119E
CAUTION
Before attempting any work on pneumatic system components, and to prevent injury, release air pressure
from the system by opening the discharge valves from all air reservoirs.
1.8.
Completely drain air from all supply reservoirs. All hoses must be cleared of air.
1.9.
Disconnect the service and parking brake hoses from the brake chambers. Make sure to mark the hoses
positions for the reinstallation.
Figure 2 - Disconnect the Hoses
1.10.
Remove both retaining nuts from the brake chamber.
Figure 3 - Remove the Two Mounting Nuts
WARNING
Do not open a brake chamber. Disassembling the brake chamber can cause injuries because of the tension
on its powerful spring. In order to prevent injuries, all discarded brake springs should be released safely.
PAGE 4 OF 8
NQF772001 VERSION 3
SERVICE BULLETIN
BS5119E
1.11.
Remove the brake chamber and dispose of the defective parts in accordance with local environmental
standards in effect.
1.12.
Before installing the new unit, the sealing surfaces must be cleaned. Apply white grease, such as Renolit
HLT2, to the spherical cup in the lever before mounting the replacement unit. See the figure below.
Figure 4 - Apply White Grease
CAUTION
Do not use grease containing molybdenum disulphate.
PAGE 5 OF 8
NQF772001 VERSION 3
SERVICE BULLETIN
BS5119E
Figure 5 - New Chamber
1.13.
Install the brake chamber with new nuts and torque to 139 ±6 lb-ft. Use hand tools only, do not use an impact
wrench. Apply torque seal. See figure 3.
1.14.
Tightened the new chamber release bolt using a 3/4'' in. wrench. Use hand tools only, do not use an impact
wrench. Torque to 55 ±5 lb-ft.
Torque to 55 ±5 lb-ft
Figure 6 - Tightened the New Chamber Release Bolt
PAGE 6 OF 8
NQF772001 VERSION 3
SERVICE BULLETIN
BS5119E
1.15.
Apply Teflon to the new elbow fittings and adapters.
1.16.
Screw the adaptor in the fitting or the elbow while firmly holding the hose-fitting nut with a wrench.
1.17.
Install the hose to the brake chamber.
1.18.
Make sure that there are no bends or kinks in the line.
1.19.
The air hose fittings should be torqued to 25 to 30 lb-ft.
1.20.
Ensure that the installation position for the fittings is correct.
Figure 7 - Install and Position Adapters and Fittings
1.21.
Repeat the steps for the chamber installation on the other side.
1.22.
Start the vehicle and recharge the pneumatic system up to a minimum pressure of 100 psi (690 kPa).
1.23.
Verify the pneumatic system’s circuit with the parking brake released.
1.24.
Apply soapy water and check for leaks, if a leak is found tightened the fittings or replace the affected parts
as per the level 2 material list.
Figure 8 - Inspect for Leaks
NOTE
It is required to test the brakes after each brake change, or as required by local regulations.
1.25.
If no leak is found, install the wheels as per your manual section 06: Wheels and tires and notify the shop
to perform brake deceleration tests.
1.26.
After the brake deceleration tests, the vehicle can return in service.
PAGE 7 OF 8
NQF772001 VERSION 3
SERVICE BULLETIN
BS5119E
LEVEL 2: PARTS THAT MAY NEED TO BE REPLACED
PN
Description
Max Qty
Additional Labor
in hour (each
part)
Justification
0.4
Replace if leak
detected. For L958,
L959, LA23, LB29,
LB59, LB99.
N95702-06
Hose assembly
(QR1-C
to
chambers)
N95702-13
Hose assembly
(QR1-C
to
chambers)
2
0.4
Replace if leak
detected. For
LA73, LA76, LB78,
LC32.
N95702-10
Hose assembly
(R14 to chambers)
2
0.4
Replace if leak
detected
N8902138
Brake lining kit (1
per axle)
1
0.75
Replace if overheat
occured
N8895746
R14 Relay Valve
1
1.5
Replace if leak
detected
N8907581
ABS modulator
2
1.5
Replace if leak
detected
N8908326
Caliper LS
1
2.0
Replace if overheat
occured
N8908325
Caliper RS
1
2.0
Replace if overheat
occured
N8900426
Caliper LS
1
2.0
Replace if overheat
occured
N8900425
Caliper RS
1
2.0
Replace if overheat
occured
N8911106
Brake disc
2
3.0
Replace if overheat
occured
2
PAGE 8 OF 8
NQF772001 VERSION 3