engine FORD F650/750 2019 Repair Manual

WARNING: Sudden accelerations
on slippery surfaces could cause the
wheels to spin, the vehicle to turn
sideways on a crowned road surface or
in a turn, possibly resulting in loss of
vehicle control and personal injury.
Activating the Locking Differential
You can lock and unlock the differential
when your vehicle is moving at a constant
speed of less than 25 mph (40 km/h) and
while the wheels are not slipping. Do not
lock the differential when your vehicle is
traveling down steep grades and when
traction is minimal.
The differential lock and differential lock
light automatically disengage at speeds
above 25 mph (40 km/h). The differential
lock remains off until either you restart your
vehicle or you turn the differential lock
switch off then back on.
Servicing a Vehicle with a Locking
Differential
Turn the engine off and raise all drive
wheels of the locker differential axle in
order to prevent your vehicle from moving
when servicing the wheels, tires or brakes.
Axles equipped with a driver-controlled
differential deliver power to both wheels
even when only one wheel is on the ground. WARNING: Failure to raise all drive
wheels with this type of differential could
cause the vehicle to move unexpectedly,
resulting in property damage, personal
injury or death. 2-SPEED REAR AXLE (IF EQUIPPED) WARNING:
Never shift a
two-speed axle when descending a
steep grade as this may cause loss of
vehicle control and result in personal
injury.
Note: Do not shift between ranges when
the speed control is on.
A two-speed rear axle allows the driver to
select a low range for greater pulling power
and a high range for greater road speed
and fuel economy. You can also use these
ranges to provide extra steps between
transmission shifts when driving on steep
grades or fuel economy may be factors.
Axle Shifting Note:
Do not shift the axle to LOW when
your vehicle is moving. Use LOW when you
drive a fully loaded vehicle on a severe grade
or in congested traffic. Use HIGH for all
normal driving conditions with a lightly
loaded or partially loaded vehicle.
Note: The axle is set to HIGH by default.
To shift the axle between HIGH and LOW
with the vehicle stopped, place the
transmission in position N, then press and
hold the button for two seconds.
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GENERAL INFORMATION
WARNING: Do not apply the brake
pedal and accelerator pedal
simultaneously. Applying both pedals
simultaneously for more than a few
seconds will limit engine performance,
which may result in difficulty maintaining
speed in traffic and could lead to serious
injury.
Note: Occasional brake noise is normal. If
a metal-to-metal, continuous grinding or
continuous squeal sound is present, the
brake linings may be worn-out. Have the
system checked as soon as possible. If your
vehicle has continuous vibration or shudder
in the steering wheel while braking, have it
checked by an authorized dealer.
All standard equipment brakes are
self-adjusting. Automatic adjustment,
when required, occurs whenever you apply
and release the brakes during forward or
reverse operation.
Know the required stopping distances for
all driving conditions you may encounter.
For longer brake lining life, take full
advantage of engine braking power when
coming to a stop.
Wet brakes result in reduced braking
efficiency. Gently press the brake pedal a
few times when driving from a car wash or
standing water to dry the brakes.
If the brakes do not grip well:
• Check brake adjustment.
• Check the brake linings for excessive
wear.
• Check the system air pressure on
vehicles with air brakes. •
Let the brakes cool if you have been
using them excessively, as in mountain
driving or after several fast, high-speed
stops.
• If you have been driving through deep
water, gently apply the brakes several
times while your vehicle is moving
slowly.
Brake Over Accelerator
In the event the accelerator pedal
becomes stuck or entrapped, apply steady
and firm pressure to the brake pedal to
slow the vehicle and reduce engine power.
If you experience this condition, apply the
brakes and bring your vehicle to a safe
stop. Move the transmission to park (P),
switch the engine off and apply the parking
brake. Inspect the accelerator pedal for
any interference. If none are found and the
condition persists, have your vehicle towed
to the nearest authorized dealer
Anti-lock Brake System
This system helps you maintain steering
control during emergency stops by keeping
the brakes from locking. This lamp momentarily
illuminates when you switch the
ignition on. If the light does not
illuminate during start up, remains on or
flashes, the system may be disabled. Have
the system checked by an authorized
dealer. If you connect a PLC trailer with
the ignition on, the trailer ABS
light also illuminates. If the light
fails to illuminate, if it remains on after you
start the vehicle or continues to flash, have
the system serviced immediately.
See
Warning Lamps and Indicators
(page 60).
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Releasing the Parking Brake
WARNING: When your vehicle is
stationary, keep the brake pedal fully
pressed when shifting gears. Failure to
follow this instruction could result in
personal injury, death or property
damage.
Note: Read and understand the following
steps and perform them whenever you
prepare to drive the vehicle.
Note: The parking brake does not disengage
unless sufficient system air pressure is
available.
1. Press and hold the service brake pedal
while the engine is running.
2. Select the appropriate drive gear.
3. Push and hold the yellow dash-mounted parking brake knob until
the parking brake light turns off, then
release.
Parking Brake Light Illumination Due
to Low Air Pressure
If the air pressure becomes too low at any
time during vehicle operation, the parking
brake may apply and the parking brake
light turns on.
If the parking brake applies due to low air
pressure, immediate service is required to
the parking brake system.
Releasing Spring Brake with Air
Pressure
The air system in all vehicles with
spring-actuated rear wheel parking brakes
has a valve on the governor for connection
to an outside air supply. The valve lets you
recharge the system with air from an
outside source, releasing the
spring-actuated parking brakes. Your
vehicle is now ready to tow in an
emergency. You can only use an outside air source if
the protected system is in operating
condition. If you cannot restore air pressure
in the protected air system, you must
release the spring-actuated brakes
manually.
Releasing Spring Manually
Do not use impact wrenches as they may
damage the piston and prevent proper
caging of the spring. Do not apply more
than
50 lb.ft (68 Nm) to the release bolt
nut.
1. Remove the stud tool and nut from the
carrying pocket on the brake chamber
assembly. 2. Remove the access plug from the end
of the spring chamber.
3. Insert the release stud through the opening in the chamber and into the
spring pressure plate. 4.
Turn the release stud ¼ 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.
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5. Tighten the nut until the spring is fully
caged and brakes released. Do not
loosen or remove the release stud and
nut unless you completely assemble
and securely clamp the brake chamber.
6. After restoring the air pressure, unscrew and remove the release stud
and install in the carrying pocket. Install
the access plug.
AIR BRAKES (IF EQUIPPED) WARNING:
Do not drive or
continue to drive if the low air pressure
buzzer is sounding or the brake warning
light is lit. These warnings indicate that
air pressure is not to normal operating
level. Continued use of the vehicle could
result in loss of braking ability. WARNING:
Avoid repeated light
application of the brake pedal. This
depletes air pressure faster and could
result in loss of braking capability. WARNING:
Do not move the
vehicle when the air pressure is
insufficient because the brake system
may be inoperative.
After starting the engine, give the air
compressor time to build up the air
pressure to
60 psi (414 kPa) before moving
your vehicle. Periodically check the air pressure gauge
while driving. Pressure should range
between approximately 100 psi (690 kPa)
to
130 psi (896 kPa). The air compressor
governor cut-in and cutout pressure
settings are set at the factory and are not
adjustable. When air pressure is insufficient
(below
60 psi (414 kPa)), a
warning light illuminates and a
buzzer sounds when the ignition is in the
on position. This may happen because
excessive brake applications are depleting
the system air pressure. If this condition
occurs, stop driving your vehicle until the
compressor has fully recharged the air
system.
Select a gear ratio to help slow your vehicle
before descending grades. Supplementing
with brakes, as required, help to safely slow
the vehicle and avoids overspeeding the
engine.
Air Chamber Stroke Indication
Air chamber push rods have orange stroke
indicator markers that warn when the
braking system requires adjustment or
repair. The painted orange indicator is on
the air chamber push rod at the slack
adjuster stroke dimension that requires
service when visible during brake
application.
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A qualified service technician should
perform air brake inspection and
adjustment or repairs keeping to the
instructions in the service manual.
Cam Brakes - Automatic Slack
Adjusters
WARNING: Do not manually
adjust the automatic slack adjusters to
correct excessive push rod stroke as it
may result in reduced brake
effectiveness and a vehicle crash.
Excessive push rod stroke indicates that
a problem exists with the automatic
adjuster, with the installation of the
adjuster, or with foundation brake
components that manual adjustment
does not remedy. Seek service from a
qualified facility for excessive push rod
stroke. Standard air brakes (cam) are equipped
with automatic brake adjusters. Automatic
adjustment occurs during brake
applications. Inspect brakes for proper
adjustment at the specified intervals. See
Scheduled Maintenance
(page 322). Emergency Air Brake WARNING:
Do not continue to
operate the vehicle with a failure of one
of the brake systems. Take the vehicle
to your dealer for service immediately.
All vehicles are equipped with a dual brake
system. In the unlikely event of a failure of
one system, the second system functions
for emergency stopping. The brake pedal
controls all these systems in the same
manner as for normal stops.
EXHAUST BRAKE
(IF EQUIPPED) WARNING:
Do not use tow/haul
when the road surface is slippery. Failure
to follow this instruction could result in
the loss of control of your vehicle. WARNING:
Do not use diesel
engine exhaust braking when the road
surface is slippery. Failure to follow this
instruction could result in the loss of
control of your vehicle.
Note: Installing an exhaust or auxiliary
brake does not necessarily protect the
engine from exceeding the maximum
governed speed. Use the primary brakes to
make sure the engine never exceeds the
maximum governed speed under any
circumstance.
Note: Before starting the engine, make sure
that the exhaust brake is off. Do not switch
the exhaust brake on until the engine has
reached normal operating temperature.
Note: Maximum exhaust brake
performance relates to the type of
transmission your vehicle has.
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Note:
Engine speed has a major influence
on limiting performance. When engine
speed stays at the maximum allowable
level, the exhaust brake operates at peak
performance.
Note: Exhaust brakes operate effectively
with automatic transmissions. However,
performance varies with engine speed and
the gear selected by the transmission.
An exhaust brake is an auxiliary braking
system that assists, but does not replace,
the primary brake system. It helps control
vehicle speed. It is not a vehicle-stopping
device.
Use the button on the instrument panel, in
combination with the accelerator pedal,
to maximize the use of the exhaust brake
in the following conditions:
• Off-highway driving.
• Mountain driving.
• Heavy traffic.
• High-speed highway driving. To switch the exhaust brake on, press the
button. A light on the instrument cluster
indicates the system is on. Press the button
again to switch it off.
While approaching a steep grade, make
sure that the exhaust brake switch is on.
The exhaust brake begins working as soon
as you remove your foot from the
accelerator pedal.
Before descending a hill or steep grade,
always select the proper gear. If you take
the transmission out of gear while
descending, you may not be able to select
another gear because of maximum
governed RPM.
Make sure the engine speed does not
exceed the maximum allowable engine
RPM. Exceeding the maximum allowable
engine RPM can 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.
While driving down a 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 use to ascend the hill.
Exhaust Brake Operating
Characteristics
The exhaust brake switches on when you
remove your feet from the accelerator
pedal and the exhaust brake is on.
If the brake is working properly, there will
be:
•
A slight change in engine sound when
the exhaust brake turns on.
• A smooth braking effect. Do not expect
a retarding effect similar to sudden,
hard application of the service brakes.
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•
A retarding force possibly felt acting
against your body during brake
application (depending on the grade
and vehicle load). This force prevents
the vehicle from going much faster.
• Engine temperatures remaining in the
normal operating range.
• A drop in engine RPM (depending on
grade and vehicle load) during a
descent.
• A decrease in road speed when
applying the exhaust brake during a
descent, except when your vehicle is
carrying a heavy load or the grade is
extremely steep. In these instances,
you may need to apply the service
brakes occasionally.
TRAILER BRAKES (IF EQUIPPED)
Trailer Brake Hand Control (If Equipped) WARNING:
The hand control
should never be used to apply the brakes
when the tractor and trailer are parked
unattended. Air may leak from the
system and the vehicle could possibly
move, resulting in possible property
damage, personal injury or death. The hand control is located on the
right-hand side of the instrument panel. It
applies the trailer service brakes, which are
independent of the truck or tractor service
brakes. It operates a valve that provides gradual
control of air pressure applied. When the
valve is only partially applied, you can
override the trailer brakes by pressing fully
on the brake pedal.
To apply the trailer brakes using the hand
control, move the lever downward. The
further you push the lever down, the
greater the air pressure is applied to the
brakes. The lever remains in place until
manually moved.
To release the trailer brakes, move the
lever up completely.
Trailer Air Supply and Parking
Brake Modular Controls
(If Equipped)
The trailer air supply valve delivers air to
the trailer supply and automatically pops
out, shutting off the trailer supply, if
pressure decreases to approximately 35 psi
(249 kPa)
.
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PRINCIPLE OF OPERATION
The traction control system helps avoid
drive wheel spin and loss of traction.
If your vehicle begins to slide, the system
applies the brakes to individual wheels
and, when needed, reduces engine power
at the same time. If the wheels spin when
accelerating on slippery or loose surfaces,
the system reduces engine power in order
to increase traction.
Note:
The system does not apply the brakes
when vehicle speed is above 25 mph
(40 km/h).
USING TRACTION CONTROL -
VEHICLES WITH: AIR BRAKES WARNING:
The stability and
traction control light illuminates steadily
if the system detects a failure. Make sure
you did not manually disable the traction
control system using the information
display controls or the switch. If the
stability control and traction control light
is still illuminating steadily, have the
system serviced by an authorized dealer
immediately. Operating your vehicle with
the traction control disabled could lead
to an increased risk of loss of vehicle
control, vehicle rollover, personal injury
and death.
Press the TCS Off button to enable the
mud/snow mode.
This is beneficial when your vehicle is stuck
in snow or on a slippery road surface. This
mode allows wheel spin to dig your vehicle
out and allows you to rock your vehicle.
Press the switch again to select standard
traction control. The system automatically
selects standard traction control at the
next ignition cycle. System Indicator Light
Note:
If the traction control light does not
flash during a traction control event or stays
illuminated, the system is not functioning
properly. Take your vehicle to an authorized
dealer for service.
During traction control operation, the
traction control light flashes rapidly and
the engine does not rev-up when you press
further on the accelerator. This is normal
and is no reason for concern.
In Mud/Snow mode, the TCS OFF light
illuminates on the instrument cluster. If a
traction event occurs in either mode, the
Stability Control and Traction Control light
flashes rapidly.
USING TRACTION CONTROL -
VEHICLES WITH: HYDRAULIC
BRAKES WARNING:
Aggressive driving in
any road conditions can cause you to
lose control of your vehicle increasing
the risk of severe personal injury or
property damage. The occurrence of a
traction control event is an indication
that at least some of the tires have
exceeded their ability to grip the road;
this may lead to an increased risk of loss
of vehicle control, vehicle rollover,
personal injury and death. If you
experience a severe road event, SLOW
DOWN.
The system automatically turns on each
time you switch the ignition on.
Use the traction control switch on the
instrument panel to switch the system off
or on.
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If your vehicle is stuck in mud or snow,
switching traction control off may be
beneficial as this allows the wheels to spin.
Press the switch again to enable the
traction control system.
System Indicator Light
Note:
If the traction control light does not
flash during a traction control event or stays
illuminated, the system is not functioning
properly. Take your vehicle to an authorized
dealer for service.
During traction control operation, the
traction control light flashes rapidly and
the engine does not rev-up when you press
further on the accelerator. This is normal
and is no reason for concern.
When traction control is disabled, the
traction control light illuminates and
flashes slowly.
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PRINCIPLE OF OPERATION
WARNING: Vehicle modifications
involving braking system, aftermarket
roof racks, suspension, steering system,
tire construction and wheel and tire size
may change the handling characteristics
of your vehicle and may adversely affect
the performance of the electronic
stability control system. In addition,
installing any stereo loudspeakers may
interfere with and adversely affect the
electronic stability control system. Install
any aftermarket stereo loudspeaker as
far as possible from the front center
console, the tunnel, and the front seats
in order to minimize the risk of interfering
with the electronic stability control
sensors. Reducing the effectiveness of
the electronic stability control system
could lead to an increased risk of loss of
vehicle control, vehicle rollover, personal
injury and death. WARNING:
Remember that even
advanced technology cannot defy the
laws of physics. It's always possible to
lose control of a vehicle due to
inappropriate driver input for the
conditions. Aggressive driving on any
road condition can cause you to lose
control of your vehicle increasing the risk
of personal injury or property damage.
Activation of the electronic stability
control system is an indication that at
least some of the tires have exceeded
their ability to grip the road; this could
reduce the operator's ability to control
the vehicle potentially resulting in a loss
of vehicle control, vehicle rollover,
personal injury and death. If your
electronic stability control system
activates, SLOW DOWN.
The system automatically turns on each
time you switch the ignition on. If a fault occurs in either the stability
control or the traction control system, you
may experience the following conditions:
•
The stability and traction control light
illuminates steadily.
• The stability control and traction
control systems do not enhance your
vehicle's ability to maintain traction of
the wheels.
Vehicles With: Air Brakes
If a driving condition activates either the
stability control or the traction control
system you may experience the following
conditions:
• The stability and traction control light
flashes rapidly.
• Your vehicle slows down.
• Reduced engine power.
The stability control system has several
features built into it to help you maintain
control of your vehicle:
Electronic Stability Control
The system enhances your vehicle ’s ability
to prevent skids or lateral slides by
applying brakes to one or more of the
wheels individually and, if necessary,
reducing engine power.
Roll Stability Control
The system enhances your vehicle ’s ability
to prevent rollovers by detecting your
vehicle ’s motion and the rate at which it
changes by applying the brakes to one or
more wheels individually.
Traction Control
The system enhances your vehicle ’s ability
to maintain traction of the wheels by
detecting and controlling wheel spin.
See
Using Traction Control (page 133).
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