INSTRUCTION TO SERVICE
ITS-61320
SECTION:

260 – Battery Compartment

SUBJECT:

Rooftop Ferrite Core Enclosure Field Retrofit

ISSUE:

ZF Center Axle A/B Bearing Failures

SUMMARY:

Install ferrite core enclosures inside rooftop inverters to eliminate excessive
CMC and subsequent center axle bearing failures.

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Ref. NHTSA Recall No.
N/A

Ref. Transport Canada Recall No.
N/A

THIS ITS DOCUMENT SHOULD BE RETAINED AND REFERRED TO FOR FUTURE MAINTENANCE UNTIL
THE NEW FLYER PARTS AND/OR SERVICE MANUAL IS UPDATED TO REFLECT WORK DONE AS A
RESULT OF THIS DOCUMENT. ENSURE THAT THIS DOCUMENT IS AVAILABLE FOR PARTS AND
MAINTENANCE STAFF GOING FORWARD.
This document and the contents discussed herein are the confidential and proprietary information of New Flyer Industries Canada
ULC and New Flyer of America Inc. and are disclosed by New Flyer in confidence. This document and the contents herein are not
to be disclosed by the intended recipient without the prior written authorization of New Flyer. Any unauthorized disclosure,
reproduction or other distribution of this document or information strictly prohibited and may result in action being taken against
the party making the unauthorized disclosure. This document and all copies hereof must be returned to New Flyer upon request.

INSTRUCTION TO SERVICE
ITS-61320

PROCEDURE:
Part A – Bus Preparation

1. Set the park brake and place wheel chocks underneath the front wheels.
2. Set the Master Run Switch to the Stop Engine position.
Caution: Wait two minutes after turning the Master Run Switch to Stop Engine, before turning the
Battery Disconnect switch OFF.
3. Turn the 12/24V battery disconnect switch to the “OFF” position. Lock and tag the switch and retain key.
4. Place the Emergency Power Disconnect switch to the “OFF” position.

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 NOTE: The Emergency Power Disconnect Switch cannot be locked out but should be switched OFF to
disconnect low voltage power to the High Voltage system.
5. Verify that the Low Voltage and High Voltage Systems are disabled. Refer to applicable section in the New
Flyer Service Manual.

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6. Remove forward inverter front cover assembly, the top covers of the inverters and the side screen panels.
Retain all hardware for reinstall. Refer to Figure 1.

 NOTE: Side screen panels (marked by #1-4 below) may be different depending on customer
specifications.
Rear inverter cover

4
2

The area where the
rear CS side screen
needs to be cut

6

1

3

Forward inverter
front cover assembly

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Figure 1 - Remove side screens on rear coach

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Forward inverter cover

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INSTRUCTION TO SERVICE
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7. The rear CS side screen needs to be cut to provide clearance for strain relief of the cables at the rear
enclosure. Refer to Figure 2.

Figure 2 – Location of the required cut out of CS side screen
8. Measure 7.18” from the forward end of the side screen then mark the 4.5” x 0.5” section as shown on the
drawing below. Carefully trim out of the edge of the side screen panel. Refer to Figure 3.

Figure 3 - Carefully trim a 4.5” x 0.5” section out of the edge of the panel

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9. Position Side Screen Cutout Plate (P/N 1116484) and use as a template to drill 0.266” (Drill size H or 17/64”)
holes at the required locations. Refer to Figure 4.

Figure 4 – Use side screen cutout bracket as a template and drill holes
10. On the inside of the side screen panel, wipe bonding surfaces with a clean lint-free cloth moistened with Sika
205 Activator (P/N 055702) to ensure that surface is dust and residue free. Apply Sika 221 (P/N 242702) to
the outside face of Cutout Support Bracket Assembly (P/N 1116443) and bond to inside face of side screen.
Ensure holes in bracket are aligned with existing holes/slots. Refer to Figure 5.
11. Apply Loctite 243 (P/N 081034) to first two threads of Hex Bolts (P/N 20B04012) x6, then install Washers
(P/N 277551) x4, and Washers (P/N 060771) x2 to secure bracket to the side screen. Refer to Figure 5.

Cutout Support Bracket P/N 1116443
glued inside of the side screen

Cutout Plate P/N 1116484

Bolts P/N 20B04012 x2 ea. and Washers P/N 060771
x2

Bolts P/N 20B04012 x4 ea. and Washers P/N 277551 x4 ea.
Figure 5 – Install side screen cutout plate to CS side screen

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Part B – Ferrite Core Enclosure Assembly


NOTE: Also refer to the applicable New Flyer drawings for buildup of Front filter core enclosure
assembly P/N 1114438 and Rear filter core housing assembly P/N 1114505 throughout this section of the
ITS.

12. Locate the bottom of core enclosure housing P/N 1114441. Refer to the details in the images below to
differentiate between the bottom and the top of the core enclosure housing.

TOP OF ENCLOSURE – Ridge
is visible beside tab bolt holes
in all four (4) corners.

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TOP OF ENCLOSURE –
Ridge is visible beside
tab bolt holes in all four
(4) corners.

TOP OF ENCLOSURE – Ridges present next to tab bolt holes in each corner

BOTTOM OF ENCLOSURE – No
ridges (flat surface) beside tab bolt
holes in all four (4) corners.

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BOTTOM OF ENCLOSURE
– No ridges (flat surface)
beside tab bolt holes in all
four (4) corners.

BOTTOM OF ENCLOSURE - Ridges NOT present (flat surface) next to tab bolt holes in each corner

13. On the bottom of the enclosure, secure Rear Core Retainment Tabs P/N 1114456 x4 with Screws P/N
505618 x4 in each corner. Apply Loctite 243 to threads of hardware and torque to 15 IN-LBS.
Rear Core Retainment
Tab P/N 1114456

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BOTTOM OF
ENCLOSURE – Secure
Rear Retainment Tabs
P/N 1114456 x4 with
Screws P/N 505618 x4 in
each corner.
Apply Loctite 243 to
threads of hardware and
torque to 15 IN-LBS.

BOTTOM OF ENCLOSURE – Install rear core retainment tabs
14. Secure White Plastic Spacer P/N 1114442 to End Spacer Plate P/N 1114443 with Screws P/N 505618 x4 and
#10 Locknuts P/N 42N00000 x4. Apply Loctite 243 to threads of hardware and torque to 15 IN-LBS.
Assembly two (2) end spacer plate assemblies.
Secure White
Spacer with
Screws P/N
505618 x4 and
#10 Locknuts
P/N 42N00000
x4.
Apply Loctite
243 to threads
of hardware
and torque to
15 IN-LBS.

Secure White Plastic Spacer to End Spacer Plate and repeat

15. Remove the backing (white paper) and install Thermal Interface Material (TIM) side shapes P/N 1115260 x2
and P/N 1114600 to one side of a Ferrite Core Ring P/N 1114606.

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

NOTE: Ensure that TIM material is applied with the adhesive side down. The top layer of the TIM has
a grey speckled pattern and is not adhesive.

TIM Shape
P/N 1115260

TIM Shape
P/N 1115260

TIM Shapes
P/N 1114600

Grey speckled pattern
indicating top (nonadhesive) layer of TIM.

Remove clear film and install TIM on one side of a ferrite core ring

16. Install the ferrite core ring into one (1) end space plate assembly with TIM shapes facing downward.

17. Using edge of end spacer plate as a guide, apply TIM strips P/N 1114603 to the outer circumference of the
ferrite core ring. GENTLY hold the ferrite core ring/end plate in a vice when applying TIM strips if necessary.



NOTE: Ensure that TIM material is applied with the adhesive side down. The top layer of the TIM has
a grey speckled pattern and is not adhesive.



NOTE: Build up 3mm of TIM with two (2) layers. FIRST layer is 2mm strips x 2 and SECOND layer is
1mm strips x2. Ensure that the second layer overlaps any gaps in TIM material around the core ring.

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Build up 3mm of TIM with
two (2) layers.
FIRST layer is 2mm
strips x 2 and SECOND
layer is 1mm strips x2.

Using metal edge of end
spacer plate as a guide,
apply TIM strips P/N
1114603 to the outer
circumference of the
ferrite core ring.

Grey speckled
pattern indicating top
(non-adhesive) layer
of TIM.

Build-up 3mm of TIM around ferrite core ring
18. Apply Polyester Film Tape P/N 1115226 around the ferrite core ring assembly. Ensure that tape clearly
overlaps the metal edge between the TIM strips and the spacer end plate.

Ensure that tape
clearly overlaps the
metal edge between
the TIM strips and
the spacer end
plate.

Apply polyester film tape around the ferrite core ring assembly.

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19. Remove clear film from top layer of TIM shapes on ferrite core ring assembly.

Ensure that TIM
material is applied
with the adhesive
side down.
Grey speckled
pattern indicating top
(non-adhesive) layer
of TIM.

CORE INSERTION OPTION 1 – Jack Screw Insertion Tool
20. Assemble Jack Screw Insertion Tool P/N 1117856. Install Plugs P/N 1117849 x2 and P/N 1117848 x2 into
Front End Plate P/N 1117846. Install Front End Plate of tool on the enclosure and secure with Socket Screws
P/N 203631 x4.



NOTE: Apply Polyester Film Tape P/N 1115226 over plugs at four (4) locations to ensure smooth core
insertion into enclosure.

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Secure with Socket
Screws P/N 203631 x4.

Apply Polyester Film Tape P/N 1115226
over plugs at four (4) locations to ensure
smooth core insertion into enclosure.
Install Front End Plate of jacking screw tool on the enclosure and secure with Socket Screws
21. Install remained of jacking screw tool on enclosure and use a 1 ¼” wrench/crow’s foot socket to turn end nut
and gently insert ferrite core ring assembly into enclosure. Do not stop until ring assembly bottoms out against
the four (4) rear core retainment tabs at the bottom of the enclosure.



NOTE: Hold the bottom of the jacking screw tool in a vice during core insertion if necessary.

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Do not stop core
insertion until ring
assembly bottoms
out against the four
(4) rear core
retainment tabs at
the bottom of the
enclosure.

CORE INSERTION OPTION 2 – Arbor Press (Preferred Option)
22. Assemble arbor press. Install Plugs P/N 1117849 x2 and P/N 1117848 x2 into Front End Plate P/N 1117846.
Install Front End Plate of tool on the enclosure and secure with Socket Screws P/N 203631 x4.



NOTE: Apply Polyester Film Tape P/N 1115226 over plugs at four (4) locations to ensure smooth core
insertion into enclosure.
23. Install Lever Press Adapter Tool P/N 1117975 and Core Press Plate P/N 1117847 on arbor press. Gently
insert ferrite core ring assembly into enclosure. Do not stop until ring assembly bottoms out against the four
(4) rear core retainment tabs at the bottom of the enclosure.

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24. Repeat process for remaining four (4) ferrite core rings. Apply TIM shapes/strips to the remaining core rings
and install into enclosure housing. Install spacer Plates P/N 1114444 x4 between core rings.
Wrap each ring assembly in Polyester Film Tape P/N 1115226 in a similar manner as before and install them
individually into the enclosure housing.

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Install Spacer Plates P/N 1114444 between core rings.
Wrap each ring assembly in Polyester Film Tape P/N
1115226 in a similar manner as before and install
them individually into the enclosure housing.

25. Lightly apply pressure to ensure that all five (5) cores are squeezed together and that core stack is sufficiently
bottomed out inside enclosure.



NOTE: DO NOT apply excessive force when squeezing core stack together with jacking screw tool or
arbor press.
26. Position the second end spacer plate assembly (previously assembled) on top of the core stack inside the
enclosure housing.
27. Use a very small Allen key to install Ball Nose Spring Plungers P/N 1114447 x4 into threaded holes in Front
Retainment Tabs P/N 1114445 x4.

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28. Install Front Retainment Tabs P/N 1114445 x4 in each corner of the top of the enclosure housing with Screws
P/N 505618 x4 in each corner. Apply Loctite 243 to threads of hardware and torque to 15 IN-LBS.

Front Retainment
Tab P/N 1114445.

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Install Front Retainment
Tabs P/N 1114445 with
Screw P/N 505618.
Apply Loctite 243 to
threads of hardware and
torque to 15 IN-LBS.

Install Ball Nose Spring
Plungers P/N 1114447 x4
into threaded holes in
Front Retainment Tabs
P/N 1114445 x4.

Position the second end
spacer plate assembly
(previously assembled) on top
of the core stack inside the
enclosure housing.

Install Front Retainment Tabs
P/N 1114445 x4 in each corner of
the top of the enclosure housing
with Screws P/N 505618 x4 in
each corner.
Apply Loctite 243 to threads of
hardware and torque to 15 INLBS.

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29. Torque Ball Nose Spring Plungers P/N 1114447 x4 until they are snuggly up to end spacer plate to firmly
secure core stack inside core enclosure housing.
30. Install rubber O-ring P/N 1114446 in grooves on both ends of core enclosure housing.



NOTE: Evenly distribute the length of O-rings inside the grooves to prevent excessive bunching/slack
in some areas.
Install rubber O-ring
P/N 1114446 on both
ends of enclosure.