793B Off-Highway Truck Caterpillar

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Hot oil and hot components can cause personal injury. Do not allow hot oil or hot components to contact the skin.

Illustration 1	g00322670

The machine must be level. The parking brake must be engaged and the engine must be stopped.

1. Remove the filler cap in order to prevent a vacuum in the tank. Install the cap after the tank has been drained. This will prevent dirt from entering the system.

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NOTICE
Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting and repair of the machine. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids. Refer to Special Publication, NENG2500, "Caterpillar Tools and Shop Products Guide", for tools and supplies suitable to collect and contain fluids in Caterpillar machines. Dispose of all fluids according to local regulations and mandates.

2. Remove the drain plug from the tank for the hoist, the torque converter and the brakes. Install a 88 mm (3.50 inch) long NPT pipe nipple in order to open the internal drain valve. The outer diameter of the NPT pipe nipple should be 25.4 mm (1 inch). Drain the oil into a suitable container.

   Note: Hand tighten the NPT pipe nipple. Do not use tools.

3. Remove the pipe nipple. Clean the drain plug and install the drain plug.

4. Remove the tank filler cap.

5. Remove the retaining ring on the filler screen. Remove the screen.

6. Wash the cap and the filler screen in clean, nonflammable solvent. Allow the cap and the filler screen to dry.

7. Inspect the cap seal. Use a new seal if the used seal is damaged. Install the filler screen and the retaining ring.

8. Fill the tank for the hoist, the torque converter and the brakes. Refer to Operation and Maintenance Manual, "Lubricant Viscosities". Refer to Operation and Maintenance Manual, "Refill Capacities" .

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Illustration 2	g00283352

9. Use the engine shutdown control to prevent the engine from starting. Crank the engine for approximately 15 seconds. The oil level will decrease as oil fills the system.

10. Add oil to the tank in order to raise the oil level to the safe starting range.

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Illustration 3	g00324184

11. Repeat Step 9 and Step 10 until the oil stabilizes in the FULL mark in the sight gauge.

12. Lower the guard on the engine shutdown control. Start the engine and operate the engine at low idle. Check for leaks and make necessary repairs.

13. Raise the dump body until the hoist cylinders are halfway extended. Lower the dump body and add oil, if necessary.

14. Raise the dump body until the hoist cylinders are fully extended. Lower the dump body and add oil, if necessary.

15. Repeat Step 13 and Step 14 until the oil level stabilizes.

16. Install the clean filler cap.