After replacing the fuel filter, the engine will purge the trapped
air as it runs. The engine may run roughly and smoke until the air
is completely eliminated.
Using a fuel which has more than average impurities may require
the fuel filter to be replaced more frequently than the service
interval specifies.
Fuel filter replacement - Cummins B engine
Refer to your engine operator’s manual for service intervals and procedures.
FUEL CONSUMPTION IMPROVEMENT MEASURES
There are two important factors you can control to improve fuel
economy: the mechanical condition of your vehicle and how you drive it.
A properly maintained vehicle will deliver better performance than a
neglected vehicle. Always follow your maintenance schedule to keep your
vehicle in top operating condition.
Also, your driving habits have a significant influence on use of fuel. By
following these suggestions, you can stretch your fuel use:
•Avoid changes in speed as much as possible.
•Anticipate changing traffic conditions. Sudden stops and fast
acceleration waste fuel.
•Avoid extensive idling.
•Do not drive with your foot resting on the brake pedal.
Essentials of good fuel economy
Measuring techniques
Your best source of information about actual fuel economy is you, the
driver. You must gather information as accurately and consistently as
possible. Fuel expense, frequency of fill-ups or fuel gauge readings are
NOT accurate as a measure of fuel economy. We do not recommend
taking fuel economy measurements during the first 1,600 km (1,000
miles) of driving (engine break-in period). You will get a more accurate
measurement after 3,000 km–5,000 km (2,000 miles-3,000 miles).
The advertised fuel capacity of the fuel tank(s) on your vehicle is equal
to the rated refill capacity of the fuel tank(s) as listed inFuel tanksin
this chapter. The advertised capacity is the amount of the Indicated
Capacity and the Empty Reserve combined. Indicated Capacity is the
difference in the amount of fuel in a full tank and a tank when the fuel
gauge indicates empty. Empty Reserve is the small amount of usable fuel
remaining in the fuel tank after the fuel gauge indicates empty.
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The amount of Empty Reserve varies and should not be relied
upon to increase driving range. When refueling your vehicle after
the fuel gauge indicates empty, you might not be able to refuel
the full amount of the advertised capacity of the fuel tank due to
the empty reserve still present in the tank.
Filling the tank
For consistent results:
•Use the same fill rate setting (low—medium—high) each time
during filling.
•Allow three automatic click-offs when filling.
•Always use fuel of a known quality, preferably a national brand.
•Have the vehicle loading and distribution the same every time.
•When refueling a vehicle equipped with dual fuel tanks, if the two
tanks are not filled equally, the fuel gauge reading may fluctuate
slightly until the fuel level between the two tanks balance out and
become equal.
Your results will be most accurate if your filling method is consistent.
Note:For vehicles equipped with dual fuel tanks, engine performance
may degrade if fuel is not added to both tanks when refueling.
Calculating fuel economy
1. Fill the fuel tank(s) completely and record the initial odometer
reading (in kilometers or miles).
2. Each time you fill the tank(s), record the amount of fuel added (in
liters or gallons).
3. After at least three to five tank fill-ups, fill the fuel tank(s) and record
the current odometer reading.
4. Subtract your initial odometer reading from the current odometer
reading.
5. Follow one of the simple calculations in order to determine fuel economy:
•Multiply liters used by 100, then divide by total kilometers traveled.
•Divide total miles traveled by total gallons used.
Keep a record for at least one month and record the type of driving (city
or highway). This will provide an accurate estimate of the vehicle’s fuel
economy under current driving conditions. Additionally, keeping records
during summer and winter will show how temperature impacts fuel
economy. In general, lower temperatures give lower fuel economy.
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