Towing With Inoperable Engine
This machine is equipped with spring-applied brakes. These brakes are released with hydraulic pressure. If the engine is inoperable or if the power train is inoperable, the parking brakes are engaged and the machine cannot be moved.
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Personal injury or death could result when towing a disabled machine incorrectly. Block the machine to prevent movement before releasing the brakes. The machine can roll free if it is not blocked. |
- When possible, engage the parking brake.
- Block the wheels.
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Illustration 1 g01157613 The diverter valve is located between the frame rails and under the center tube.
The wheels have been removed for ease of viewing.Show/hide table
Illustration 2 g01157612 - A diverter valve (tow valve) is located on the rear of the hydraulic tank. The diverter valve must be shifted in order to provide supply oil to the parking brake release valve.
Loosen two clamp bolts (1) on the diverter valve and slide the plate and the spool (2) to the left. After the spool is shifted, tighten clamp bolts (1). This will allow supply oil to flow to the parking brake release valve.
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Illustration 3 g00629767 - Attach a 8T-0857 Pressure Gauge and a line in pressure tap (3) on the right rear wheel.
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NOTICE When towing the machine, attach tow line to the front tow hooks or rear tow pin only.
- Hook up the towing machine. Refer to Operation and Maintenance Manual, "Towing the Machine" for guidelines.
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In order to prevent possible personal injury, release the air pressure from the air tank before disconnecting any components of the air system.
Show/hide tableNOTICE Do not exceed the air pressure of
830 ± 35 kPa (120 ± 5 psi) or damage can occur to the air system components.Note: The air pressure in the air system must be at
550 kPa (80 psi) in order to allow the supply oil to disengage the parking brakes. - If there is not sufficient air pressure in the air system, the air system can be charged with air from another source.
- Before you attempt to charge the system, remove the air pressure from the brake system.
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Illustration 4 g00793334 - Remove plug (4) from the air tank for the service brake and the retarder. Install a quick disconnect fitting.
- Connect a hose from an outside air supply to the fitting on the air tank. Charge the reservoirs to at least
550 kPa (80 psi) . Do not exceed830 ± 35 kPa (120 ± 5 psi) . - Remove the supply hose.
- Before you attempt to charge the system, remove the air pressure from the brake system.
- Disengage the parking brake.
Note: Make sure that the parking brake reset valve is depressed.
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Illustration 5 g00629769 - An electric drive pump provides supply oil pressure in order to disengage the parking brakes. This pump also supplies oil to the secondary steering system. Press switch (5) in order to activate the brake release and secondary steering pump. Hold switch (5) until the pressure on the pressure gauge that was installed in Step 4 stops rising.
- Apply the service brake on the disabled machine in order to check the braking. If the brakes are functioning, release the brakes.
- While you depress switch (5) for the brake release and secondary steering pump, rotate the steering wheel to each side in order to check the steering.
- Remove the blocks from the wheels.
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NOTICE Do not allow oil pressure to drop below
2760 kPa (400 psi) while towing.Partial brake engagement could occur and can result in brake damage. Brakes must be fully released when towed machine is moving.
- Pull the disabled machine with the towing machine. During towing, continue to watch the pressure gauge that was installed in Step 4. Do not continue to tow the machine if the oil pressure is below
2760 kPa (400 psi) .
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