2002 FORD F650 brakes

4. Turn the release stud one-quarter
turn to engage the stud tangs with
the slot in the pressure plate. Keep
the stud engaged and install the nut
on the release stud.
5. Tighten the nut until the spring is
fully caged and the brakes are
released. Do not loosen or remove
the release stud and nut unless the brake chamber is completely
assembled and is securely clamped.
6. When the air pressure is restored, unscrew and remove the release
stud and install in the carrying pocket. Install the access plug.
Trailer brake (if equipped)
During normal operation, the trailer
brakes operate whenever the tractor
brakes are applied. A manual control
lever is provided so the trailer
brakes can be applied separately, if
required. To apply the trailer brakes,
pull the trailer brake control
downward to the APPLIED position.
Do not use the trailer brake
manual control lever for
parking.
Trailer air supply control (MV-3) (Tractor package)
The MV-3 control module is a two-button, push-pull control valve housed
in a single body which includes a dual circuit supply valve and a check
valve.
Operation
During initial charge, with the system completely discharged, both
buttons are out.
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When a trailer is hooked-up
correctly and system pressure
reaches 448 kPa (65 psi), the red
control (trailer supply) may be
pushed in and should stay in,
charging the trailer system and
releasing the trailer brakes.
The yellow control (parking brake)
may now be pushed in, which will
supply air to the tractor spring
brakes, releasing them.
Normal operating position
With both controls pushed in, air is supplied to the trailer and to the
tractor spring brakes; all brakes are released.
Actuation of trailer parking or emergency brakes
To actuate the trailer brakes only,
pull out the red control (trailer air
supply), exhausting the trailer
supply line. The trailer brakes are
now applied either by air emergency
or spring brakes, depending on the
type of trailer system. This mode
would be used to uncouple from the
trailer during bob-tail operation.
TRAILER
AIR SUPPLY
NOT FOR PARKING
PULL
TO
TOEVACUATE
PUSH
SUPPLY
PARKING
BRAKE
PULL
TOAPPLY
PUSH
TORELEASE
TRAILER
AIR SUPPLY
NOT FOR PARKING
PULL
TO
TOEVACUATE
PUSH
SUPPLY
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System park
With both controls in for normal run modes, the parking brakes on both
tractor and trailer may be actuated by pulling the yellow control (parking
brake) out, which exhausts the air from the tractor spring brakes and
simultaneously causes the red control (trailer supply) to pop out,
applying the trailer brakes. This complies with federal regulations stating
one control must apply all the parking brakes on the vehicle.
Trailer charge
If both controls are out when parking the combination vehicle and it is
desired to recharge the trailer (leaving the tractor spring brakes
applied), the trailer air supply control may be pushed in, repressurizing
the trailer supply line. This mode could also be used to park a
combination vehicle with air actuated emergency brakes on the trailer to
provide demonstrated parking capability with tractor spring brakes only.
Automatic application
With both controls in (in the normal run configuration), if the supply
pressure to the push-pull valves is reduced to approximately 240 to 310
kPa (35-45 psi), the red control (trailer supply valve) must pop out,
applying the emergency or parking brakes on the trailer. If the red
control is held in manually and the pressure decreases to approximately
172 to 240 kPa (25-35 psi), a tripper piston within the MV-3 valve will
move upward. This will exhaust the trailer supply, causing the required
non-override feature. The yellow control (parking brake) will pop out at
approximately 138 to 207 kPa (20-30 psi).
Reservoir selection
The number one service reservoir will at all times be selected as the
primary supply source for the MV-3. This is accomplished automatically
by the function of the dual circuit supply valve contained in the body of
the MV-3. Only in the event of a pressure drop of more than 207 kPa (30
psi) below that of the number two service reservoir will the dual circuit
supply valve shuttle and establish the front service reservoir as the
supply.
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Exhaust brake (if equipped)
An exhaust brake is an optional
auxiliary braking system that assists
but does not replace the primary
service brake system. An on-off
switch on the instrument panel, in
combination with the accelerator
and clutch pedal switches, allows
the operator to make maximum use
of the exhaust brake in the
following conditions:
²off-highway driving
²mountain driving
²heavy traffic
²high speed highway driving
It is not available with automatic transmissions.
The exhaust brake is a butterfly
type valve mounted in the exhaust
pipe. When the operator's foot is not
on the accelerator pedal and the
exhaust brake switch is in the ON
position, an air cylinder shuts the
butterfly valve, restricting the flow
of exhaust gases and retarding the
engine. This retarding action is
carried through the engine and drivetrain, slowing the vehicle and
reducing the need for frequent service brake applications.
Exhaust brakes are not intended for use as the primary braking system
during vehicle operation.
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127

Operation
Push the rocker switch up to turn
the exhaust brake on. The switch
will illuminate in the ON position.
Push the switch down to turn the
brake off.
Starting engine
Before starting the engine, make sure that the exhaust brake switch is in
the OFF position. Do not turn the exhaust brake on until the engine has
reached normal operating temperatures.
Driving downhill
While approaching a steep grade, make sure that the exhaust brake
switch is in the ON position. The exhaust brake actuates as soon as you
remove your foot from the accelerator pedal. While going down the
grade, use a low enough gear to descend safely with a minimum
application of the service brakes. As a general guideline, use the same
gear as you would to ascend the hill.
Before descending a hill or steep grade always select the proper gear. If
the transmission is taken out of gear while descending it is possible that
you will not be able to select another gear because of maximum RPM
being governed.
Make sure the engine speed does not exceed the maximum allowable
engine RPM. Exceeding the maximum allowable engine RPM will result
in damage to the engine. Apply the service brakes to reduce the engine
RPM or make a slower descent by using a lower gear.
The exhaust brake is not recommended for use on slippery or
low traction road surfaces. Under these conditions a loss of
vehicle control could possibly occur.
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Exhaust brake operating characteristics
When you remove your feet from both the accelerator and clutch pedals
and the exhaust brake switch is in the ON position, the exhaust brake is
activated. The following conditions should exist if the brake is operating
properly:
²A slight change in the sound of the engine when the exhaust brake is
activated.
²Exhaust smoke appears normal.
²Engine temperature remains in the normal operating range.
²Road speed usually decreases when the exhaust brake is applied
during a descent, except when the vehicle is carrying a heavy load or
the grade is extremely steep. In these instances, you may need to
apply the service brakes occasionally.
²During a descent, the tachometer usually shows a drop in RPM
depending on the grade and the vehicle load.
²Do not expect a retarding effect similar to sudden hard application of
the service brakes. The exhaust brake retards the vehicle with a
smooth braking effect.
²Depending on the grade and vehicle load, you may or may not feel the
retarding force acting against your body when the brake is applied.
The brake's retarding force is actually preventing the vehicle from
going much faster.
Make sure the exhaust brake is turned off before shutting off the engine.
Installing an exhaust or auxiliary brake should never allow the
engine to exceed maximum governed speeds under any
conditions.
Air brake reservoir draining
Failure to drain air brake reservoirs can result in a reduction or
loss of braking ability due to fluid accumulation in the reservoir
and/or possible freeze-up during cold weather.
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129

engine should be at idle speed when any shift from N (Neutral) to a
drive range is made.
The N (Neutral) position may also be used during stationary operation of
the Power Take-Off (PTO), if equipped.
Do not allow your vehicle to coast in N (Neutral). Engine
braking is not available in N (Neutral). Allowing your vehicle to
coast in N (Neutral) may result in loss of vehicle control and severe
internal transmission damage.
D (DriveÐNormal driving position)
In this position, the transmission starts in first gear and automatically
shifts through second, third, fourth and fifth depending on load and
speed demands. When the vehicle is slowing down, the transmission will
automatically downshift. This range is used for highway driving under
normal conditions.
4 and 2 (Fourth and Second)
Use this position when road, load or traffic conditions make it desirable
to restrict the automatic shifting to a lower range. These ranges provide
greater engine braking than D (Drive). When conditions no longer
require these lower gears, shift back to D (Drive).
1 (First)
The transmission has to be manually shifted into 1 (First) and will not
shift into a higher gear. Use this position when pulling through mud or
snow, driving up steep grades, hauling extra heavy loads or where
maximum reduction is required.
Power take-off (PTO) operation with an Allison automatic
transmission (except MD applications and vehicles equipped with
a Caterpillar 3126E engine)
The power take-off can be operated while the vehicle is standing or
moving.
To engage the PTO, apply the brakes and shift to any gear other than N
(Neutral) - this stops the rotation of the PTO drive gear in the
transmission - then engage the PTO.
If engagement is prevented by the gear teeth not meshing properly,
release the brakes and allow the vehicle to creep slightly - or shift the
selector to N (Neutral) and then back in gear. The PTO should never be
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139

hubs (for trucks) or the bottom of the wheel rims (for cars).
Once through the water, always try the brakes. Wet brakes do not stop
the vehicle as effectively as dry brakes. Drying can be improved by
moving your vehicle slowly while applying light pressure on the brake
pedal.
Driving through deep water where the transmission vent tube is
submerged may allow water into the transmission and cause
internal transmission damage.
MAXIMUM VEHICLE LOADING
Every vehicle manufactured by Ford
Motor Company is supplied with
information on the Vehicle Rating
Decal listing the maximum loading
for the vehicle (GVWR), and its axle
systems (GAWR) at the tire to
ground interface.
Under no circumstances should your vehicle be loaded in excess of the
GVWR or GAWR. It is the operator's responsibility to assure that neither
the axle capacities, spring capacities, tire capacities nor the vehicle rated
GVWR is exceeded. For tire capacities, refer toMaintenance and
specificationschapter.
Unloaded or lightly loaded vehicles
The braking system has been designed to safely stop your vehicle when
fully loaded to its GVWR.
When operating empty or lightly loaded, sudden or hard braking
may induce wheel lockup with loss of vehicle control and the
possibility of accident and serious injury, especially on wet or slippery
road surfaces.
MFD. BY FORD MOTOR CO. IN U.S.A.
WB TYPE/GVW BODY TRANS AXLE EXT PNT DSO
XXX XXXXXX XXX XXX XXX XXXX XXXXXX
ÑFOHT-15294A10-GA
DATE: XXXXX GVWR:XXXXX LB/ XXXXX KGFGAWR: XXXXXX/XXXXXXX RGAWR: XXXXXXX/XXXXXXX
XXXXXXXXXXXX W/TIRES XXXXXXXXXXXX W/TIRES
XXXXXXXXX RIMS XXXXXXXXX RIMS
AT XXX PSI COLD AT XXX PSI COLD
THIS VEHICLE CONFORMS TO ALL APPLICABLE FEDERAL
MOTOR VEHICLE SAFETY STANDARDS IN EFFECT ON THE
DATE OF MANUFACTURE SHOWN ABOVE.
VIN: XXXXXXXXXXXXXXXXX REAR REAR GAWR
TYPE: XXXXXXXXXXXXXXXXXX XXXXXXX/XXXXXXX
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