SERVICE BULLETIN

Service Bulletin
American Honda Motor Co., Inc.
2001-2015 GL1800/A, GL1800B/BD SECONDARY MASTER CYLINDER REPLACEMENT
GL1800 #23 - REPAIR PROCEDURE
Service Bulletin
American Honda Motor Co., Inc.
SAFETY RECALL
OVERVIEW ·················································· 1-2
PEDAL BRAKE LINE FLUID FLUSHING ···· 1-9
PEDAL BRAKE LINE FLUID DRAINING ····· 1-2
PEDAL BRAKE LINE FLUID FILLING ······· 1-12
REPLACE THE REAR M ASTER CYLINDER 1-4
PEDAL BRAKE LINE AIR BLEEDING ······· 1-14
REM OVE THE FRONT WHEEL··················· 1-7
CHECK THE REPAIR ································· 1-14
REM OVE THE SECONDARY M ASTER
CYLINDER ··················································· 1-8
IDENTIFICATION ······································ 1-14
’12-’15 GL1800
GL1800B/BD
©2015 American Honda M otor Co., Inc. – All Rights Reserved
M TB 15624 (1510)
1
GL1800 #23 - REPAIR PROCEDURE
GL1800 #23 - REPAIR PROCEDURE
OVERVIEW
OBJECTIVE
This repair procedure, when properly executed, will eliminate most contaminants from the pedal brake system
prior to the installation of the secondary master cylinder (SMC) parts kit.
The procedure differs significantly from the Service Manual brake filling/bleeding sequence, as it includes a
fluid flushing procedure and the installation of a new rear master cylinder (to ensure all contaminants are
removed from the pedal brake line) before the final fluid filling and bleeding. Carefully review the complete
procedure before starting. AHM will issue Service Manual revision pages to update the Service Manual with the
new brake fluid replacement procedure.
Use only the provided Pro Honda DOT 4 brake fluid from sealed containers to ensure the quality of the
repair procedure.
PARTS, SUPPLIES, AND TOOLS
REQUIRED
In addition to common hand tools, the brake fluid replacement procedure requires the following parts, supplies
and tool:
– Master cylinder kit, second/rear (For model application, see the PARTS INFORMATION section of this
bulletin.)
P/N 06454-MCA-306 (1) or
P/N 06454-MJG-306 (1)
– Use only Pro Honda DOT 4 brake fluid (6 bottles per repair) Initially, automatically shipped separately from
the parts kit.
– Applicable Service Manual
– Commercially available brake bleeder
TRIKE CONVERSIONS or MODIFIED
BRAKES
If the vehicle is a trike conversion, or has a modified, disabled, or removed secondary master cylinder (SMC)
and the SMC is non-functional, note these facts on the R.O. and contact TechLine for further instructions.
PEDAL BRAKE LINE FLUID DRAINING
Spilling fluid can damage painted, plastic or rubber
parts. Place a shop towel over these parts whenever
the system is serviced.
• Do not mix different types of fluid. They are not compatible.
• Do not allow foreign material to enter the system when filling the reservoir.
PEDAL BRAKE LINE FLUID DRAINING
RIGHT FRONT CALIPER
SECONDARY
MASTER CYLINDER
REAR MASTER CYLINDER
DELAY
VALVE
ANTI-DIVE
PLUNGER
PCV
LEFT FRONT
CALIPER
2
REAR
CALIPER
GL1800 #23 - REPAIR PROCEDURE
Refer to the Service Manual and remove the following:
[2]
– right engine side cover
– front fender A, both fender covers, and front fender
B
– rear fender A
Support the motorcycle on its centerstand or a lift.
Remove the bolt [1] and rear master cylinder reservoir.
Remove the rear master cylinder reservoir cap [2], set
plate [3], and diaphragm [4].
Temporarily install the reservoir and tighten the bolt.
[1]
Connect a commercially available brake bleeder [1] to
the bleed valve of the pedal brake line as shown.
Loosen the bleed valve and activate the brake bleeder
until no more fluid flows out of the bleed valve.
Close the bleed valve.
Perform the fluid draining procedure at each remaining
valve of the pedal brake line in the following order:
1.
2.
3.
4.
[3]/[4]
[1]
Right front caliper:
Rear caliper:
right front caliper, lower: [1]
rear caliper, lower: [2]
anti-dive plunger: [3]
rear caliper, upper: [4]
[1]
[2]
Rear caliper:
Anti-dive plunger:
[4]
[3]
3
GL1800 #23 - REPAIR PROCEDURE
REPLACE THE REAR MASTER
CYLINDER
REMOVAL
Remove the two screws and brake light/cruise cancel
switch (’13 – ’14 GL1800B: brake light switch) assembly
[1] from the master cylinder.
[1]
Remove the two bolts [2] and right footpeg [3].
[4]
[2]
Remove the pinch bolt [4] and brake pedal [5].
When removing the
hose and oil bolt,
cover the ends of
the hoses to
prevent
contamination.
Remove the reservoir hose [1] from the master cylinder
[2].
[5]
[3]
[4]
[3]
Disconnect the brake hose by removing the oil bolt [3]
and sealing washers [4].
[2]
[2]
[1]
Unhook the spring end to remove the return spring [1]
from the frame and pivot arm [2].
[4]
[3]
Release the drive shaft joint boot [3] from the engine.
Remove the master cylinder mounting bolts [4].
Remove the pedal pivot arm from the frame while
pushing the water hose aside, then remove the master
cylinder/pivot arm assembly [5].
[5]
[2]
4
[1]
GL1800 #23 - REPAIR PROCEDURE
Remove the following from the master cylinder:
[1]
– split pin [1]
– joint pin [2]
– pivot arm [3]
[3]
[2]
CLEAN THE RESERVOIR
AND OIL BOLT
Use a wire brush if
necessary to clean
the oil bolt threads.
Thoroughly clean the reservoir [1], hose [2], and oil bolt
[3] with WATER only. DO NOT USE BRAKE
CLEANER!
[3]
[1]
Blow all components dry with compressed air.
[2]
INSTALLATION
MASTER CYLINDER
OIL BOLT
SEALING WASHERS
PIVOT ARM
BRAKE LIGHT/CRUISE CANCEL
SWITCH ASSEMBLY
RETURN SPRING
RIGHT FOOTPEG
BRAKE PEDAL
5
GL1800 #23 - REPAIR PROCEDURE
Install the pivot arm [1] into the new master cylinder
push rod joint with the joint pin [2] and a new split pin
[3].
[3]
[1]
Apply grease to the pivot shaft groove of the pivot arm
[1].
[2]
[2]
[3]
[4]
Place the master cylinder/pivot arm assembly [2] into
the frame while pushing the water hose and driveshaft
joint boot aside, then insert the pivot arm into the pivot
hole, being careful not to damage its splines.
Install the master cylinder onto the frame and tighten
the mounting bolts [3].
TORQUE: 12 N·m (1.2 kgf·m, 9 lbf·ft)
Install the joint boot [4] onto the engine.
Install the return spring [5] into the pivot arm and onto
the frame stopper pin in the direction shown.
[1]
Install the reservoir hose [1] onto the joint.
[5]
[3]
[2]
Connect the brake hose to the master cylinder with the
oil bolt [2] and new sealing washers [3], and tighten the
oil bolt.
TORQUE: 34 N·m (3.5 kgf·m, 25 lbf·ft)
[1]
Install the brake pedal [1] by aligning the slit with the
punch mark on the pivot arm.
[2]
Install the pinch bolt [2] and tighten it.
TORQUE: 27 N·m (2.8 kgf·m, 20 lbf·ft)
Align
[1]
6
GL1800 #23 - REPAIR PROCEDURE
Install the footpeg [1] and tighten the bolts [2].
[2]
TORQUE: 27 N·m (2.8 kgf·m, 20 lbf·ft)
[1]
Apply locking agent to the threads of the switch holder
screws.
Install the brake light/cruise cancel switch (’13 – ’14
GL1800B: brake light switch) assembly [1] with the
screws.
Adjust the switch position so that the brake light comes
on when pushing the brake pedal slightly and the push
rod moves 0.7 – 1.7 mm.
Tighten the switch holder screws.
[1]
TORQUE: 1.5 N·m (0.2 kgf·m, 1.1 lbf·ft)
REMOVE THE FRONT WHEEL
Refer to the Service Manual, remove the front wheel.
7
GL1800 #23 - REPAIR PROCEDURE
REMOVE THE SECONDARY MASTER
CYLINDER
REMOVAL
Remove the following:
When removing the
oil bolt, cover the
joints of the hoses
to prevent
contamination.
Airbag models:
[1]
– oil bolt (upper side) and sealing washers [1]
– upper side brake hose(s) [2]
– brake hose joint attaching bolt [3]
Non-airbag
models:
[1]
[4]
Loosen the oil bolt (front side).
Remove the following:
–
–
–
–
mounting bolts [4]
oil bolt (front side) and sealing washers [5] (discard)
front side brake hose [6]
secondary master cylinder [7] (discard)
[2]
[3]
[4]
[3]
[2]
[5]
[7]
[6]
PLUG THE BRAKE HOSES
Install the washers (reuse), oil bolts [1], and provided
cap nuts [2] to the brake hoses as shown.
Tighten the cap nuts securely.
[1]
[2]
8
GL1800 #23 - REPAIR PROCEDURE
TEMPORARILY REINSTALL THE
FRONT WHEEL
Temporarily reinstall the front wheel and hand tighten
the axle nut [1].
Temporarily reinstall the brake calipers and hand
tighten the bolts [2].
[2]
[1]
PEDAL BRAKE LINE FLUID FLUSHING
FLUID FLUSHING
• Use only the provided Pro Honda DOT 4 brake
fluid from sealed containers to ensure the
quality of the repair procedure.
[1]
• It is not a problem if the fluid flowing out of the bleed
valve contains air bubbles because the lines will be
bled in later steps (AIR BLEEDING).
Fill the reservoir [1] with only Pro Honda DOT 4 brake
fluid from a sealed container.
Operate the brake pedal [2] several times until the
brake fluid level in the reservoir goes down.
[2]
Connect a commercially available brake bleeder to the
upper side bleed valve [1] of the left front caliper.
Activate the brake bleeder and loosen the bleed valve.
• Check the reservoir fluid level often while filling the
brake to prevent air from being pumped into the
system. If air is entering the bleeder from around the
bleed valve threads, seal the threads with Teflon
tape.
If an automatic refill system is not used, add brake fluid
when the fluid level in the reservoir is low.
[1]
Repeat above procedure until a sufficient amount of
clean fluid flows out of the bleed valve.
Close the bleed valve.
• When using a brake bleeding tool, follow the
manufacturer’s operating instructions.
9
GL1800 #23 - REPAIR PROCEDURE
Perform the flushing procedure at each bleed valve in
the sequence as follows:
[2]
1. Right front caliper lower side bleed valve [2]
2. Rear caliper lower side bleed valve [3]
[3]
Manual pumping is
required to ensure
all contaminants
are removed from
the pedal brake
line.
Manually pump (no vacuum bleeder) another 200 cc of
fluid through each bleed valve in sequence; [1], [2], [3].
[2]
– Fill the reservoir to the UPPER level line.
– Pump the fluid through the bleed valve by operating
the pedal until the fluid comes down to the LOWER
level line.
– Repeat the procedure eight (8) times to pump about
200 cc (approx. 7 oz) through the system.
Use a graduated cylinder as a catch basin for manual
pumping to measure the amount of flushed brake fluid.
Drain the fluid from the system, with the brake bleeder
tool, through each bleed valve in sequence; [1], [2], [3].
[1]
[3]
TEMPORARILY REMOVE THE
FRONT WHEEL
Temporarily remove the front brake calipers and front
wheel.
10
GL1800 #23 - REPAIR PROCEDURE
INSTALL THE NEW SECONDARY
MASTER CYLINDER
Remove the cap nuts that were installed on the brake
hoses earlier.
Airbag models:
Non-airbag models:
[2]
Connect the front side brake hose [1] to the master
cylinder with the oil bolt [2] and new sealing washers
[3].
[2]
Install the new secondary master cylinder onto the fork
leg with the mounting bolts [4] and tighten them.
[6]
TORQUE: 30 N·m (3.1 kgf·m, 22 lbf·ft)
Tighten the oil bolt (front side).
[3]
[6]
TORQUE: 34 N·m (3.5 kgf·m, 25 lbf·ft)
[3]
Install the brake hose joint and tighten the bolt [5].
TORQUE: 12 N·m (1.2 kgf·m, 9 lbf·ft)
Connect the upper side brake hose(s) [6] to the master
cylinder with the oil bolt and new sealing washers, and
tighten the oil bolt.
[3]
TORQUE: 34 N·m (3.5 kgf·m, 25 lbf·ft)
[2]
[4]
[1]
[5]
REINSTALL THE
FRONT WHEEL
Refer to the Service Manual, reinstall the front wheel
and brake calipers.
Tighten all hardware to the specified torque values.
Do not reinstall the front fender at this time.
11
GL1800 #23 - REPAIR PROCEDURE
PEDAL BRAKE LINE FLUID FILLING
• Use only the provided Pro Honda DOT 4 brake
fluid from sealed containers to ensure the
quality of the repair procedure.
• Feed fluid into the pedal brake line in the following
sequence:
1. Left front caliper, upper side bleed valve [1]
2. Right front caliper, lower side bleed valve [2]
3. Rear caliper, lower side bleed valve [3]
4. Anti-dive plunger bleed valve [4]
5. Rear caliper, upper side bleed valve [5]
[1]
[5]
Left front caliper:
[3]
[4]
[2]
Rear caliper:
Anti-dive plunger:
Right front caliper:
FLUID FILLING
• It is not a problem if the fluid flowing out of the bleed
valve contains air bubbles because the lines will be
bled in later steps (AIR BLEEDING).
[1]
Fill the reservoir [1] with only Pro Honda DOT 4 brake
fluid from a sealed container.
Operate the brake pedal [2] several times until the
brake fluid level in the reservoir goes down.
[2]
12
GL1800 #23 - REPAIR PROCEDURE
Connect a commercially available brake bleeder to the
upper side bleed valve [1] of the left front caliper.
Activate the brake bleeder and loosen the bleed valve.
• Check the reservoir fluid level often while filling the
brake to prevent air from being pumped into the
system. If air is entering the bleeder from around the
bleed valve threads, seal the threads with Teflon
tape.
[1]
If an automatic refill system is not used, add brake fluid
when the fluid level in the reservoir is low.
Repeat the above procedure until a sufficient amount of
clean fluid flows out of the bleed valve.
Close the bleed valve.
• When using a brake bleeding tool, follow the
manufacturer’s operating instructions.
Perform the above procedure at each bleed valve in the
sequence as follows:
[2]
1. Right front caliper lower side bleed valve [2]
2. Rear caliper lower side bleed valve [3]
3. Anti-dive plunger bleed valve [4]
4. Rear caliper upper side bleed valve [5]
[3]
[4]
[5]
Manual pumping is
required to ensure
all contaminants
are removed from
the pedal brake
line.
Manually pump (no vacuum bleeder) another 200 cc
(approx 7 oz) of fluid through each bleed valve in
sequence:
[4]
1. Anti-dive plunger bleed valve [4]
2. Rear caliper upper side bleed valve [5]
– Fill the reservoir to the UPPER limit line.
– Pump the fluid through the bleed valve by operating
the pedal until the fluid comes down to the LOWER
level line.
[5]
– Repeat the procedure eight (8) times to pump about
200 cc (approx. 7 oz) through the system.
Use a graduated cylinder as a catch basin for manual
pumping to measure the amount of flushed brake fluid.
13
GL1800 #23 - REPAIR PROCEDURE
PEDAL BRAKE LINE AIR BLEEDING
MANUAL AIR BLEEDING
• Use only the provided Pro Honda DOT 4 brake
fluid from sealed containers to ensure the
quality of the repair procedure.
• Note that you may feel strong resistance on the
brake pedal during pumping to bleed air from the
right front caliper. This is caused by the activation of
the delay valve. Be sure to depress the brake pedal
fully to the bottom.
• The air bleeding procedure must be performed in the
same way as in the fluid filling procedure without
using a brake bleeder tool.
Repeat this procedure until air bubbles no longer
appear in the plastic overflow hose at each bleed
valve.
After air bubbles cease to appear in the fluid, repeat
the air bleeding procedure 2 to 3 times.
• Make sure that the bleed valves are closed and
operate the brake pedal. If it still feels spongy, bleed
the system again.
• After bleeding the air completely, tighten the bleed
valves.
TORQUE: 5.4 N·m (0.6 kgf·m, 4.0 lbf·ft)
Fill the reservoir to the upper level line with only Pro
Honda DOT 4 brake fluid from a sealed container.
Remove the bolt [1] and reservoir then install the
diaphragm [2], set plate [3] and reservoir cap [4] to the
reservoir.
Install the reservoir and tighten the bolt securely.
[4]
Clean up any spilled brake fluid with soapy water.
Install the following:
– front fender B, both fender covers, and front fender
A
– rear fender A
[1]
[2]/[3]
CHECK THE REPAIR
Confirm that all bleed valves are tight and there are no
leaks.
Check the pedal brake operation.
IDENTIFICATION
After you have completed the entire repair procedure,
apply a punch mark on the rear master cylinder lower
mounting tab as shown.
Install the right engine side cover.
14
PUNCH MARK