2003 FORD F750 overheating

Engine coolant temperature gauge
Indicates the temperature of the
engine coolant. At normal operating
temperature, the needle remains
within the normal area (the area
between the“H”and“C”). If it
enters the red section, the engine is
overheating. Stop the vehicle as
soon as safely possible, switch off
the engine immediately and let the
engine cool. Refer toEngine
coolantin theMaintenance and
specificationschapter.
Never remove the coolant reservoir cap while the engine is
running or hot. Steam and scalding liquid from a hot cooling
system can burn you badly.
This gauge indicates the temperature of the engine coolant, not the
coolant level. If the coolant is not at its proper level the gauge indication
will not be accurate.
Engine oil pressure gauge
Indicates engine oil pressure. At
normal operating temperature, the
needle will be in the normal range
(the area between the“L”and“H”);
if the needle goes below the normal
range, stop the vehicle as soon as
safely possible and switch off the
engine immediately. Check the oil
level. Add oil if needed (refer to
Engine oilin theMaintenance
and specificationschapter). If the oil level is correct, have your vehicle
checked at your dealership or by a qualified technician.
H
C
L
H
Instrumentation
16

To prevent electrical shock, do not use your heater with
ungrounded electrical systems or two-pronged (cheater)
adapters.
Operating the engine
Do not operate the engine at full throttle below peak torque engine
speed (RPM) for more than one minute at a time (peak torque RPM
varies from 1200-1500 RPM depending on engine rated speed).
Monitor the oil pressure and coolant
temperature gauges frequently.
If the gauges indicate any reading is
not in the normal operating range,
stop your vehicle as soon as possible,
shut the engine off and check the
appropriate fluid level. If an
overheating condition starts to occur,
release the throttle pressure or shift
the transmission into a lower gear, or
both, until the temperature returns to normal operating range.
Continuous operation with low
coolant temperature, below 60°C
(140°F) or high coolant temperature
100°C (212°F) can damage the
engine.
Most failures give some kind of early
warning. Look and listen for changes
in performance, sound or engine
appearance that can indicate service
or engine repair is needed. Some
changes to look and/or listen for:
•Engine misfires
•Loss of power
•Sudden changes in engine operating temperature or oil pressure
•Excessive smoke
•Fuel, oil or coolant leaks
•Vibration
•Increased oil or fuel consumption
L
H
H
C
Driving
111

Gold Engine Coolant (yellow-colored), VC-7–A (VC-7–Bin
Oregon), depending on the type of coolant originally equipped
in your vehicle.If you are unsure which type of coolant your vehicle
requires, check your coolant reservoir or contact your local dealer.
Note:Use of Motorcraft Cooling System Stop Leak Pellets, VC-6,
darkens the color of Motorcraft Premium Gold Engine Coolant from
yellow to golden tan.
•Do not add/mix an orange-colored, extended life coolant such
as Motorcraft Speciality Orange Engine Coolant, VC-2 (US) or
CXC-209 (Canada), meeting Ford specification WSS-M97B44–D
with the factory-filled coolant.Mixing Motorcraft Speciality Orange
Engine Coolant or any orange-colored extended life product with your
factory filled coolant can result in degraded corrosion protection.
•A large amount of water without engine coolant may be added, in case
of emergency, to reach a vehicle service location. In this instance, the
cooling system must be drained and refilled with a 50/50 mixture of
engine coolant and distilled water as soon as possible. Water alone
(without engine coolant) can cause engine damage from corrosion,
overheating or freezing.
•Do not use alcohol, methanol or brine or any engine coolants
mixed with alcohol or methanol antifreeze (coolant).Alcohol
and other liquids can cause engine damage from overheating or
freezing.
•Do not add extra inhibitors or additives to the coolant.These
can be harmful and compromise the corrosion protection of the engine
coolant.
•Do not mix with recycled coolant unless from a Ford-approved
recycling process (seeUse of Recycled Engine Coolantsection).
For vehicles with overflow coolant systems with a non-pressurized cap
on the coolant recovery system, add coolant to the coolant recovery
reservoir when the engine is cool. Add the proper mixture of coolant and
water to the“cold full”level. For all other vehicles, which have a coolant
degas system with a pressurized cap, or if it is necessary to remove the
coolant pressure relief cap on the radiator of a vehicle with an overflow
system, follow these steps to add engine coolant.
To reduce the risk of personal injury, make sure the engine is
cool before unscrewing the coolant pressure relief cap. The
cooling system is under pressure; steam and hot liquid can come out
forcefully when the cap is loosened slightly.
Maintenance and Specifications
188

1. Before you begin, turn the engine off and let it cool.
2. When the engine is cool, wrap a thick cloth around the coolant
pressure relief cap on the coolant reservoir (an opaque plastic bottle).
Slowly turn cap counterclockwise (left) until pressure begins to release.
3. Step back while the pressure releases.
4. When you are sure that all the pressure has been released, use the
cloth to turn it counterclockwise and remove the cap.
5. Fill the coolant reservoir slowly with the proper coolant mixture (see
above), to within the“cold fill range”or the“cold full”level on the
reservoir. If you removed the radiator cap in an overflow system, fill the
radiator until the coolant is visible and radiator is almost full.
6. Replace the cap. Turn until tightly installed. (Cap must be tightly
installed to prevent coolant loss.)
After any coolant has been added, check the coolant concentration see
Checking Engine Coolant section). If the concentration is not 50/50
(protection to–34°F/–36°C), drain some coolant and adjust the
concentration. It may take several drains and additions to obtain a 50/50
coolant concentration.
Whenever coolant has been added, the coolant level in the coolant
reservoir should be checked the next few times you drive the vehicle. If
necessary, add enough 50/50 concentration of engine coolant and
distilled water to bring the liquid level to the proper level.
If you have to add more than 1.0 liter (1.0 quart) of engine coolant per
month, have your dealer check the engine cooling system. Your cooling
system may have a leak. Operating an engine with a low level of coolant
can result in engine overheating and possible engine damage.
Replacing coolant
A coolant mixture of 50% coolant concentrate and 50% water is
recommended to maintain best overall performance. To avoid damaging
the engine and radiator, the coolant concentrate should not exceed 60%.
When refilling the coolant system either as part of the regular
maintenance (refer to the general maintenance information section), or
due to service performed, adhere to the following instructions:
1. Drain and flush the cooling system to remove dirt deposits, oil, rust
particles.
Note:
When filling the system with Motorcraft Premium Engine Coolant
(green-colored) or equivalent meeting Ford specification ESE-M97B44–A, a
supplemental coolant additive is required. Refer toAdding Coolantsection
Maintenance and Specifications
189