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a buildup of heavy deposits of carbon and rust on valve stems causing
them to stick which, in turn, can cause valvetrain damage.
Winter fronts
The use of winter fronts, or other air-restrictive devices mounted in front
of the radiator on vehicles with chassis-mounted charge air coolers, are
not recommended unless extremely cold weather conditions exist. Air
flow restriction can cause high exhaust temperatures, power loss,
excessive fan usage and a reduction in fuel economy. If you must use a
winter front, the device should have a permanent opening of at least 120
sq in. (774 sq. cm) directly in line with the fan hub.
Hot weather operation
•Keep the engine cooling system filled with a clean, permanent coolant
solution to protect against damage from overheating.
•Fill the fuel tank at the end of daily operation to prevent condensation
in the fuel system.
•Keep external surfaces of the engine, radiator, charge air cooler, A/C
condenser and accessories clean to avoid dirt build-up.
Above normal coolant temperatures could be experienced while driving
in a transmission gear ratio which lugs the engine. To correct this
problem, engine speed should be increased by downshifting in to the
next lower gear to increase engine RPM.
Starting a turbocharged engine with the vehicle on a steep grade
When starting a diesel engine when the loaded vehicle is on a grade, the
engine RPM will start to fall slightly when the clutch is engaged; do not
disengage the clutch and try to increase engine RPM as this may damage
driveline components. The engine will recover as the vehicle begins
moving.
Engine shutdown
Allow the engine to idle for three to five minutes before shutting it
down. The larger the engine, the greater the need for this idling period.
However, do not let the engine idle for more than 10 minutes.
Restarting after running out of fuel
The fuel system may need to be purged of air, refer toRunning out of
fuelin theMaintenance and Specificationschapter.
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Supplement
USA(fus)
Driving
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•Check for proper operation of radiator shutters, if equipped. The
shutters should be open during normal operating temperatures.
Engine and Driveline System
•Transmission Enclosure:inspect for cracks, holes, and tears. Clean
any deposits such as oil, dirt, and stones.
•Engine valve covers and block covers are made to damp out engine
mechanical noise and, if needed, should be replaced with
recommended parts. Check for mechanical isolations.
Exhaust System
•Inspect the exhaust system for leaks at various joint connections and
tighten the clamps.
•Do a visual inspection for cracks or holes in the muffler and tail pipe.
•Always use the recommended parts when items need to be replaced.
•The tail pipe elbow or offset tail pipe orientation must not be changed
from the standard position as originally received.
•To avoid abnormal changes in vehicle sound levels, it is necessary for
the owner to perform inspections and necessary maintenance at the
intervals shown in theScheduled Maintenance Guidechapter.
POWER STEERING FLUID
Check the power steering fluid level using the following procedure. If
adding fluid is necessary, refer toLubricant Specificationsin this
chapter for the proper fluid type. Refer to theScheduled Maintenance
Guidechapter for the recommended service intervals.
1. Set the parking brake, shift into N (Neutral) (automatic transmission)
or 1 (First) (manual transmission) and turn the engine off.
2. Open the hood.
3. Clean the top of the power steering fluid reservoir.
4. Remove the dipstick from the reservoir and wipe the dipstick clean.
5. Reinstall the dipstick. Remove it again and check the fluid level.
2008 F-650/750(f67)
Supplement
USA(fus)
Maintenance and Specifications
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Maintenance Operation Frequency - Observation
Check the engine performance
and the engine governorExcessive engine noise.
Inspect the fan, the fan shroud,
and the fan clutchEngine overheats, fan runs at high
speed constantly, excessive fan noise,
or fan wobble due to worn bearings.
Check for operation of ABS
warning lampAt each engine start up.
Inspect the entire exhaust
system (including inlet pipe,
muffler, outlet pipe and all
exhaust clamps and fasteners)
for holes, leakage, breakage,
looseness and corrosive
damageExcessive noise or the smell of fumes
is experienced.
Inspect the engine air
induction system (including the
air ducts and the air filter) for
loose fitting, damaged or
missing componentsExcessive noise emanates from the
engine compartment.
Inspect the tires and check the
air pressure
(3)Poor steering, wandering or excessive
tire wear.
Balance the wheels and the
tiresVibration or abnormal tire wear
indicates imbalance.
Check the front end alignment
(3)Poor steering, wandering or excessive
tire wear.
Check the transmission and
engine mountings
(2)Hard shifting or excessive vibration.
Check and adjust transmission
controls
(2)High effort to shift or noisy
transmission.
Check fuel pump pressure Insufficient full-throttle power or
backfiring.
Clean radiator cap seal. Clean
and inspect the cap surface on
the radiatorWhen the cap does not hold pressure.
2008 F-650/750(f67)
Supplement
USA(fus)
Scheduled Maintenance Guide
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