793C Off-Highway Truck Caterpillar

1. The warning light for low brake air pressure will cause the alert indicator to flash. The instruction “Do Not Move Machine” will appear in the message center. This instruction will remain until the service air tank is charged to approximately 1/2 of the maximum operating pressure. If the parking brake is switched to the OFF position and the brake air pressure is less than half of the operating pressure, the operator will be warned by the action alarm.
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   Illustration 1	g00688521

2. Before you operate the machine, monitor message center (1) of the Vital Information Management System (VIMS). Take action on any events that are displayed.

   Note: In order to provide maximum sound suppression, keep all of the doors closed and keep all of the windows closed.

3. With the engine at low idle and with the oil at normal operating temperature, check the oil levels of the following systems: engine, steering, transmission and hoist, torque converter and brake. Refer to the Maintenance Section for information on checking the oil levels.

4. Check the horn. Check the backup alarm. Check any other warning devices on the machine.

5. Check the operation of the steering and the brakes. Check the secondary brake. Do not operate the machine if any discrepancies are found.
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   Illustration 2	g00688520

6. Frequently observe messages, warnings, service lights, and all gauges (2). All gauges should be at normal operating range. The alert indicator, the action light and the action alarm should be off.

7. Adjust the operator's seat. Adjust the mirrors.

8. Fasten the seat belt.
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   Do not allow a companion to ride on the machine unless the companion is seated within the Rollover Protective Structure (ROPS) with the seat belt fastened. The companion must have the seat belt fastened while the machine is in operation. Personal injury or death may occur if the companion is not restrained and protected.

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   Illustration 3	g00637355

9. Lower the body. Place the hoist control in FLOAT position (3).
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   Illustration 4	g00688532

10. Retarder control (lever) (4) should be in the UP position.
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    Illustration 5	g00688530

11. Switch (5) for the ARC should be in the ON position.
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    Illustration 6	g00688542

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    Illustration 7	g00688543

12. Depress service brake control (pedal) (8). Disengage parking brake release switch (7). Move transmission control (6) to the desired direction and the desired gear.

    Note: Only operate the controls if the engine is running.

13. Release service brake control (pedal) (8) and depress accelerator control (pedal) (9).

Preparing to operate the machine

1. Do not attempt to move the machine without normal brake air pressure.

2. In order to prevent injury, make sure that no one is working on the machine or near the machine. Keep the machine under control at all times in order to prevent injury.

3. Know the maximum height of the machine. Know the maximum width of the machine. Maintain proper clearance.

4. Only operate the machine if the engine is running.

5. Before the machine operates at a high speed, check the operation of the brake system and of the steering system. These systems should be checked while the machine maintains a low speed.

6. Make sure that the Automatic Retarder Control (ARC) operates properly before you travel down a grade with a machine that is loaded. Test the ARC on a short grade before the machine is loaded.

7. In order to prevent injury, make sure that no one is working on the machine or near the machine. Keep the machine under control at all times in order to prevent injury.

8. Reduce engine speed when you are maneuvering in tight quarters or when you are driving over a rise.

Reference: For further operating information, See Operation and Maintenance Manual, "Loading", Operation and Maintenance Manual, "Hauling", and Operation and Maintenance Manual, "Dumping".