octane FORD F650/750 2021 Owners Manual

The Vehicle Warranty may not cover
repairs needed to correct the effects of
using an aftermarket product that does
not meet our specifications in your fuel.
FUEL QUALITY - GASOLINE
Choosing the Right Fuel
Your vehicle is designed to operate on
regular unleaded gasoline with a minimum
pump (R+M)/2 octane rating of 87.
Some fuel stations, particularly those in
high altitude areas, offer fuels posted as
regular unleaded gasoline with an octane
rating below 87. The use of these fuels
could result in engine damage that will not
be covered by the vehicle warranty.
We do not recommend these fuels. For
best overall vehicle and engine
performance, premium fuel with an octane
rating of 91 or higher is recommended. The
performance gained by using premium fuel
is most noticeable in hot weather as well
as other conditions, for example when
towing a trailer. See Towing a Trailer
(page 171).
Do not be concerned if the engine
sometimes knocks lightly. However, if the
engine knocks heavily while using fuel with
the recommended octane rating, contact
an authorized dealer to prevent any engine
damage. We recommend Top Tier detergent
gasolines, where available to help minimize
engine deposits and maintain optimal
vehicle and engine performance. For
additional information, refer to
www.toptiergas.com.
Note:
Use of any fuel for which the vehicle
was not designed can impair the emission
control system, cause loss of vehicle
performance, and cause damage to the
engine which may not be covered by the
vehicle Warranty.
Do not use:
• Diesel fuel.
• Fuels containing kerosene or paraffin.
• Fuel containing more than 10% ethanol
or E85 fuel.
• Fuels containing methanol.
• Fuels containing metallic-based
additives, including manganese-based
compounds.
• Fuels containing the octane booster
additive, methylcyclopentadienyl
manganese tricarbonyl (MMT).
• Leaded fuel, using leaded fuel is
prohibited by law.
The use of fuels with metallic compounds
such as methylcyclopentadienyl
manganese tricarbonyl (commonly known
as MMT), which is a manganese-based
fuel additive, will impair engine
performance and affect the emission
control system.
RUNNING OUT OF FUEL -
DIESEL
Avoid running out of fuel. This allows air to
enter the fuel system and may make it
difficult to restart your vehicle.
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F650750 (TBC) , enUSA, Edition date: 202010, Second-Printing Fuel and RefuelingE161513

Dual Alternator Dual Alternator With Air Brake
Compressor
Drivebelt closest to the engine.
A
Drivebelt furthest from the
engine.
B
Note: The belt routings show vehicles with
air conditioning. When vehicles do not have
air conditioning, an idler pulley is in place of
the A/C compressor.
ENGINE SPECIFICATIONS - 7.3L 7.3L V8 Engine
Engine
445 in³ (7,293 cm³)
Displacement.
Minimum 87 octane
Required fuel.
1-5-4-8-6-3-7-2
Firing order.
Coil near spark plug with spark plug wire
Ignition system.
0.049 in (1.25 mm) - 0.053 in (1.35 mm)
Spark plug gap.
10.5:1
Compression ratio.
282
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