freightliner 108SD 2021, Driver Manual

Page: 54 / 191

WARNING
Hydraulic clutch control fluid (DOT 4 brake fluid)
is hazardous. It may be a skin irritant and can
cause blindness if it gets in your eyes. Always
wear safety glasses when handling it or bleeding
hydraulic lines. If you get it on your skin, wash it
off as soon as possible.
NOTICE
Do not spill hydraulic clutch control fluid on the
cab paint. Clean it off immediately if any is spilled.
Brake fluid can damage paint.
IMPORTANT: The pressure line must slope con-
tinuously downward between the master and
slave cylinders. On some vehicles, the securing
clamps may need to be removed to achieve this
and allow the air to be purged.
Pressure Bleeding
NOTE: A bleeder system (J-29532) and a bleed
adaptor (J-35798) for the fluid reservoir are
available through SPX Kent-Moore Tools and
may be used to complete the following proce-
dure. To order these parts, call Kent-Moore at
1-800-328-6657.
1. Park the vehicle on a level surface, shut down
the engine, and set the parking brake. Chock the
tires and raise the hood.
2. Prepare the pressure bleeding equipment ac-
cording to the manufacturer’s instructions. Use
new DOT 4 brake fluid from a tightly sealed con-
tainer. Pressurize the bleeder system to 15 psi
(103 kPa).
3. Remove the reservoir lid (see Fig. 4 ) and install
the pressure bleed adaptor on the reservoir.
4. Bleed the hydraulic system as follows.
4.1 Open the bleed valve on the bleed tank
to pressurize the reservoir.
4.2 Remove the cap from the bleed valve of
the slave cylinder. See
Fig. 5 . On the
valve, install a transparent drain hose
connected to a catch bottle. The hose
needs to fit the bleed valve tight enough
so it does not fall off when fluid is
pumped out.
4.3 Open the bleed valve on the slave cylin-
der.
4.4 When the draining fluid is clear and free
of air bubbles, close the bleed valve.
5. Check the fluid level in the reservoir. If neces-
sary, add or drain fluid to bring the fluid level to
between the MIN and MAX lines marked on the
side of the reservoir. Install the reservoir lid.
6. Disconnect the transparent hose. Tighten the
bleed screw 88 lbf·in (1000 N·cm) and install the
cap on the slave cylinder bleed valve.
7. Depress the clutch pedal a few times. There
should be resistance over the full pedal stroke.
Manual Bleeding
1. Park the vehicle on a level surface, shut down
the engine, and set the parking brake. Chock the
tires and open the hood.
NOTE: The hydraulic system holds approxi-
mately 0.5 quart (0.5 liter) of fluid. It may need
to be refilled during the bleeding process to pre-
vent air from re-entering the system.
2. Remove the reservoir lid and fill the reservoir
(see
Fig. 4 ) with new DOT 4 brake fluid from a
tightly sealed container.
3. Remove the cap from the bleed valve of the
slave cylinder. See
Fig. 5 . On the valve, install a
11/30/2010 f250682
1
2
1. Bleed Valve 2. Slave Cylinder
Fig. 5, Slave Cylinder, Hydraulic Clutch Control
Clutch
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108SD and 114SD Maintenance Manual, September 2015
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