SMB-151 – Front & Rear Disc Brake Installation – New Flyer

SEOCONTENT-START

SMB-151 1 of 7
SERVICE MANUAL BULLETIN
This Service Manual Bulletin is prepared by the Publications Department of New Flyer Industries
Canada ULC. Refer to details below.
The New Flyer vehicles described in this manual may be protected by one or more
patents and design applications or registrations in the United States and Canada,
and in other countries. Refer to “Vehicle Patent Information” in this manual.
Copyright © 2015 New Flyer Industries Canada ULC
ISSUE DATE: Jul 16 2015
SMB-151
APPLICABILITY
VEHICLE LENGTH  30ft.  35ft.  40ft.  60ft.  ALL
VEHICLE TYPE  High Floor  Low Floor  Invero®  Xcelsior®  ALL
FUEL TYPE
 Diesel  Electric  CNG  LNG
 ALL
 Diesel/Electric  Gas/Electric  Fuel Cell
SUBJECT Front & Rear Disc Brake Installation
SECTION TITLE 1 – Front Axle & Suspension
2 – Rear Axle & Suspension
DETAILS This bulletin provides additional revised OEM information on various
installations pertaining to the front and rear disc brakes.
Refer to your New Flyer Service Manual for complete information.
This information supersedes any prior information on this subject already
provided in your New Flyer Service Manuals. Make this Service Bulletin
available to service personnel to inform them of changed information.
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2 of 7 SMB-151
SERVICE MANUAL BULLETIN
SMB-151
The New Flyer vehicles described in this manual may be protected by one or more
patents and design applications or registrations in the United States and Canada,
and in other countries. Refer to “Vehicle Patent Information” in this manual.
Copyright © 2015 New Flyer Industries Canada ULC
1. FRONT & REAR BRAKE
SYSTEM
1.1. Installation
Due to the danger of injury when working
with heavy components, ALWAYS
use assistance when moving or lifting
the wheel hub.
1.1.1. Mounting the Wheel Hub
Apply a light coat of Molykote-D paste in
the wheel hub bearing seat area and on
the axle stub. Apply paste on the machined
surface of the stub where the hub bearings
are seated except 3/4″ of inner bearing
seat.
1.1.2. Disc Brakes Specifications & Wear
Limits
Brake Pad Clearance……… 0.024 to 0.043″
(0.6 to 1.1 mm)
Brake Pad Thickness (min)……………. 0.08″
(2.0 mm)
1.1.3. Automatic Adjustment Inspection
The installed adjuster adapter must be
used when turning the adjuster. The
adjuster adapter is designed with a
shear point so as to prevent excessive
force from being applied to the internal
adjustment mechanism and causing
possible damage.
1. Remove the protective cap from the
adjuster by pulling on the tab. Do not use a
screwdriver or similar tool to remove the
cap, as damage to the sealing lip could
occur.
NEVER turn adjuster without shear
adapter being installed. If the shear
torque of the shear adapter is
exceeded, it is designed to fail. If shear
adapter fails, try again using a new
(unused) shear adapter. With a second
failure of the shear adapter, the caliper
must be exchanged since internal damage
is present.
DO NOT use an open-ended wrench as
this may damage the adapter.
2. Rotate the adjuster adapter one half turn
(approx. 3 clicks) counter-clockwise using
a 10 mm wrench. See “Fig. 1: Checking
Adjuster Movement” on page 3.
3. Position a 10 mm box end wrench on the
adjuster adapter so that the wrench is
positioned close to the vertical position.
4. Actuate the brake treadle 5 times with
approximately 30 psi (2 bar) brake application
pressure and note the movement of
the installed wrench.
5. The wrench should move in a clockwise
direction in response to each brake application,
until clearance is taken up.
☞NOTE:
The angle of turn or movement of the
wrench decreases or slows as the number
of steps rises.
6. Replace the brake caliper if the automatic
adjuster does not operate properly.
Improper operation is indicated by either:
a. No movement.
b. Movement on the first brake application
only.
c. Moves CCW then CW on each brake
application.
7. Lubricate seal lip and reinstall protective
cap. Position the tab so that it will be
accessible for future removal and not be
obscured by the brake chamber.
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SMB-151 3 of 7
SERVICE MANUAL BULLETIN
SMB-151
The New Flyer vehicles described in this manual may be protected by one or more
patents and design applications or registrations in the United States and Canada,
and in other countries. Refer to “Vehicle Patent Information” in this manual.
Copyright © 2015 New Flyer Industries Canada ULC
Fig. 1: Checking Adjuster Movement
1.1.4. Caliper Guide Pin Inspection
☞NOTE:
Worn caliper guide pins will result in excessive
movement in the caliper assembly relative
to the brake carrier. Use the following
procedure to determine if excessive wear
is present:
1. Remove worn brake pads and temporarily
replace with a set of new pads during this
procedure. Refer to your New Flyer Service
Manual for removal procedure.
☞NOTE:
Perform brake pad inspection on the
removed pad. Refer to your New Flyer Service
Manual for procedure. Replace pads
as necessary or reinstall existing pads.
2. Push the caliper inward fully the pull the
caliper outward fully. Movement of the caliper
on the guide pins should be smooth
throughout the full range of movement
(approximately 1.0″ (25 mm)). Replace the
caliper guide pins if the full range of movement
cannot be achieved or if excessive
force is required to move the caliper.
3. Check for excessive play in the caliper
guide pins as follows:
a. Pull the caliper fully outward.
b. Mount a dial indicator (Items 29 & 69
from special tools list) on the steering
knuckle with the indicator tip resting on
the leading edge of the brake caliper.
Apply pressure to the brake caliper in
an upward direction. Zero the dial
gauge. See “Fig. 2: Measuring Guide
Pin Play” on page 3.
c. Apply pressure to the brake caliper
leading edge in a downward direction
and read the dial gauge. Replace guide
pins if reading exceeds 0.079″ (2.0
mm). Refer to your New Flyer Service
Manual for replacement procedure.
Fig. 2: Measuring Guide Pin Play
DETAIL A
ROTATION
ADJUSTER
ADAPTER
10MM
WRENCH
A
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DIAL INDICATOR TIP
BRAKE CALIPER
LEADING EDGE
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4 of 7 SMB-151
SERVICE MANUAL BULLETIN
SMB-151
The New Flyer vehicles described in this manual may be protected by one or more
patents and design applications or registrations in the United States and Canada,
and in other countries. Refer to “Vehicle Patent Information” in this manual.
Copyright © 2015 New Flyer Industries Canada ULC
1.1.4.1. Installation
DO NOT grease the brake pad guides as
this will cause abraded material from
brake pad to accumulate and prevent
smooth movement of the brake pads in
the guide.
1. Push the brake caliper inward against the
stop and insert the inboard brake pad. See
See “Fig. 3: Brake Pad Installation” on
page 5.
2. Pull the brake caliper outward against the
stop and insert the outboard brake pad.
3. Insert the wear sensor cable into the
groove of each pad. The wear indicators
snap into place in the holes in the pad
material.
☞NOTE:
Ensure that the longer end of the wear
sensor harness is inserted into the outboard
brake pad.
☞NOTE:
The wear sensor cable should be replaced
any time a brake wear condition has been
detected. Typically the wear sensor will be
abraded and damaged whenever it triggers
a worn brake pad condition. It is also recommended
that the wear sensor cable be
replaced whenever the disc brake pads are
renewed.
4. Install the brake pad retainer as follows:
a. Insert the inboard end of the pad
retainer into the groove and apply sufficient
downward pressure to allow insertion
of the retaining pin. See “Fig. 4:
Brake Pad Retainer Installation” on
page 5.
b. Insert new retaining pin and secure
with new washer and spring clip.
5. Attach the wear sensor harness guide to
the brake pad retainer and clip the sensor
harness to secure it.
6. Install the wear sensor harness protection
plate onto the brake pad retainer.
7. Attach the wear sensor harness to the
brake caliper using the original mounting
bolt and nut. Apply medium strength
threadlocker, such as Loctite-242, to the
threads of the nut.
☞NOTE:
If the round sensor connector between the
wear sensor harness and the extension
harness is unplugged during the removal
procedure, check that the rubber seal is
not damaged or deformed. Ensure the
wear sensor connector is properly pushed
into the cable extension connector upon re
installation. The cable extension connector
has locking tabs which lock in position
when the sensor’s plug is inserted correctly.
A damaged seal or improperly seated
connector will not provide a watertight
seal between the sensor connector and
the extension cable connector. Penetration
of water can lead to corrosion on
connector pins and cause sensor failure.
8. Adjust the brake pad clearance as follows:
a. Use the adjuster adapter and turn the
adjuster clockwise until the pads touch
the brake disc surface.
b. Turn the adjuster back three notches as
confirmed by audible clicks.
c. Actuate the brakes 10 times with minimum
30 psi (2 bar) applied brake pressure.
This action will automatically take
up any clearance and provide the
desired running clearance.
d. Verify the actual clearance by prying
against the inboard brake pad backing
plate and using a feeler gauge to measure
clearance between the backing
plate and tappet. Clearance should be
0.027 to 0.047″ (0.7 to 1.2 mm).
9. Lower the vehicle and perform road test to
verify satisfactory operation of the brakes.
DRAFT
SMB-151 5 of 7
SERVICE MANUAL BULLETIN
SMB-151
The New Flyer vehicles described in this manual may be protected by one or more
patents and design applications or registrations in the United States and Canada,
and in other countries. Refer to “Vehicle Patent Information” in this manual.
Copyright © 2015 New Flyer Industries Canada ULC
Fig. 3: Brake Pad Installation
Fig. 4: Brake Pad Retainer Installation
1.1.5. Tappet Rubber Boot Inspection
DO NOT adjust the tappets beyond
1.18″ (30 mm) as measured from the
surface of the caliper to the tappet
thrust face. Turning any further will
result in irreparable damage to the
adjuster adapter. Penetration of dirt and
moisture into the interior of the brake
will lead to corrosion and impair the
function of the clamping mechanism
and the adjusting mechanism.
1. Remove the brake pads. Refer to your New
Flyer Service Manual for removal procedure.
2. Rotate the adjuster clockwise until the tappets
extend approximately 1.18″ (30) from
the caliper surface. This will allow full
extension of the tappet rubber boot for a
proper visual inspection. See “Fig. 5: Tappet
& Rubber Boot Inspection” on page 6.
3. Inspect the rubber boot for proper seating,
wear, cuts, or deterioration. Replace rubber
boots as necessary. Refer to your New
Flyer Service Manual for replacement procedure
4. Inspect the tappet thrust surface for scoring,
corrosion, or other damage. Replace
tappets as necessary. Refer to your New
Flyer Service Manual for replacement procedure.
CALIPER
INBOARD
BRAKE PAD
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RETAINING
PIN
BRAKE PAD
RETAINER
WASHER SPRING
CLIP
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6 of 7 SMB-151
SERVICE MANUAL BULLETIN
SMB-151
The New Flyer vehicles described in this manual may be protected by one or more
patents and design applications or registrations in the United States and Canada,
and in other countries. Refer to “Vehicle Patent Information” in this manual.
Copyright © 2015 New Flyer Industries Canada ULC
Fig. 5: Tappet & Rubber Boot Inspection
1.1.5.1. Installation
☞NOTE:
This procedure can be performed with the
caliper mounted to the axle or on a work
bench. The special tools used contain two
different length bolts depending on the
method used. For installation on a work
bench, use the longer bolt. For on-vehicle
installation, use the shorter bolt.
1. Rotate the adjuster counter-clockwise until
the threaded tubes are fully retracted
within the caliper bore.
2. Thread the long forcing bolt into the
installer sleeve (Item 82 from special tools
list). See “Fig. 6: Installing Inner Seal” on
page 7.
3. Place the new inner seal onto the press-in
bushing (Item 83 from special tools list).
4. Place the assembled press-in bushing and
inner seal into the installer sleeve. Use the
forcing bolt to press the inner seal against
the stop in the brake caliper.
5. Rotate the adjuster clockwise until the end
of the threaded sleeve extends 0.59″ (15
mm) from the caliper surface.
☞NOTE:
The inner seal must not turn.
6. Apply grease, supplied in the repair kit,
onto the end of the threaded sleeves and
install new bushings.
7. Turn the adjuster counter-clockwise until
the threaded sleeves are fully retracted
within the caliper bore.
1.18 INCH
(30MM)
RUBBER BOOT
`
TAPPET
TAPPET
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SMB-151 7 of 7
SERVICE MANUAL BULLETIN
SMB-151
The New Flyer vehicles described in this manual may be protected by one or more
patents and design applications or registrations in the United States and Canada,
and in other countries. Refer to “Vehicle Patent Information” in this manual.
Copyright © 2015 New Flyer Industries Canada ULC
8. Place the tappet and rubber boot onto the
bushing.
☞NOTE:
Ensure the seal seat is clean and free from
grease before installing the rubber boot
into the seal seat.
9. Hold the installer sleeve (Item 82 from special
tools list) against the rubber boot and
use the long forcing bolt to press the rubber
boot against the stop in the seat. See
“Fig. 7: Installing Tappet & Rubber Boot”
on page 7.
10.Reverse the position of the installer sleeve
so that the open end is facing away from
the tappet and boot assembly and the
head of the forcing bolt is facing the tappet.
See “Fig. 8: Seating Tappet Against Stop”
on page 7.
11.Use the forcing bolt to press the tappet up
against the stop on the threaded sleeve.
12.Install the brake pads. Refer to your New
Flyer Service Manual for installation procedure.
Fig. 6: Installing Inner Seal
Fig. 7: Installing Tappet & Rubber Boot
Fig. 8: Seating Tappet Against Stop
1. Threaded Tube
2. Forcing Bolt
3. Installer Sleeve
4. Inner Seal
5. Press-In Plate
6. Seal Seat
7. Brake Caliper
1
2
3
4
5
6
7
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1. Threaded Tube
2. Forcing Bolt
3. Installer Sleeve
4. Tappet & Rubber Boot
5. Bushing
6. Seal Seat
1
2
3
4
5
6
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TAPPET
FORCING
BOLT
INSTALLER
SLEEVE
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