Blue Bird Coachworks 450 LXi, Owner'S Manual

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450 LXi Owner Manual 3-1 Starting and Driving
~ 3-1-3 ~ Rev. “C”
3-1.5.2 Fuel and the Effect from Cold Weather
The following fuels are in the grades that are available for Caterpillar engines:
No. 1
No. 2
Blend of No. 1 and No. 2
No. 2 diesel fuel is the most commonly used fuel. Either No. 1 diesel fuel or a blend of No. 1 and No. 2 is best suited for cold
weather operation.
Quantities of No. 1 diesel fuel are limited. No. 1 diesel fuels are usually available during the months of the winter in the
colder climates. During cold weather operation, if No. 1 diesel fuel is not available, use No. 2 diesel fuel, if necessary.
There are three major differences between No. 1 and No. 2 diesel fuel. No. 1 diesel fuel has the following properties:
Lower cloud point
Lower pour point
Lower rating of BTU per unit volume of fuel
When No. 1 diesel fuel is used, a decrease in power and in fuel effi ciency may be noticed. Other operating effects should not
be experienced.
The cloud point is the temperature when a cloud of wax crystals begins to form in the fuel. These crystals can cause the fuel
fi lters to plug. The pour point is the temperature when diesel fuel will thicken. The diesel fuel becomes more resistant to fl ow
through fuel pumps and through fuel lines.
Be aware of these values when diesel fuel is purchased. Anticipate the average ambient temperature of the area that the
engine will be operated. Engines that are fueled in one climate may not operate well if the engines are moved to another
climate. Problems can result due to changes in temperature.
Before troubleshooting for low power or for poor performance in the winter, check the type of fuel that is being used.
When No. 2 diesel fuel is used the following components provide some means of minimizing problems in cold weather:
Starting aids
Engine oil pan heaters
Engine coolant heaters
Fuel heaters
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NOTICE: Failure to open the winter fronts in the morning could cause engine damage and/or loss of fuel
economy.
3-1.5 Cold Weather Operation
3-1.5.1 Radiator Restrictions
Caterpillar discourages the use of airfl ow restriction devices that are mounted in front of radiators. Airfl ow restriction can
cause the following conditions:
High exhaust temperatures
Power loss
Excessive fan usage
Reduction in fuel economy
Shutters can be properly used for parking overnight, very cold temperatures, and high winds. In those particular cases, the
coolant temperature and the inlet manifold temperature must be carefully monitored and controlled.
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