422E, 428E, 432E, 434E, 442E and 444E Backhoe Loaders Caterpillar

Lowering the Loader Bucket

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Personal injury or death can result from a bucket falling. Keep personnel away from the front of the machine when lowering the bucket.

Lowering the Loader without Electrical Power

If there is no electrical power, the loader cannot be lowered to the ground with the control lever. Perform the following steps in order to manually lower the loader:

Note: Two people are needed in order to manually lower the loader. One person should be used in order to ensure that all personnel are clear of the machine while the loader is being lowered.

1. Turn the engine start switch key to the ON position.

2. Ensure that the parking brake is engaged.

3. Ensure that the hydraulic lockout switch is in the UNLOCKED position.

4. Turn the ride control switch to the OFF position.

   Note: If your machine is not equipped with a ride control switch, a dead engine lower switch will be installed. A second person will be required in order to hold the dead engine lower switch.

   Note: The loader control valve is located under the machine on the right side of the machine.

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   Illustration 1	g01381769

5. Remove the pilot control line and remove the fitting from the bottom of the lift valve on the loader control valve.

6. Fully install the 308-4547 Valve Adjuster.

7. Turn in by hand the screw of the 308-4547 Valve Adjuster, until the tool contacts the spool.

8. Use a suitable tool in order to turn the center of the 308-4547 Valve Adjuster by 90 degrees increments. When the loader begins to lower, allow the loader to lower slowly, in order to ensure the loader is under control.

9. When the loader has been fully lowered, remove the 308-4547 Valve Adjuster. Reconnect the pilot control line to the valve section.

10. Make the necessary repairs before you operate the machine.

Lowering the Loader with a Hydraulic Component Failure

If a break in a hydraulic line has occurred, perform the following steps in order to lower the lift arms to the ground.

Illustration 2	g02047754

The load control valve for the loader is located on each lift cylinder.

Illustration 3	g00514917

1. Install a 6 mm (0.25 inch) hose onto the purging screw. Route the other end of the hose into a suitable container in order to drain the oil.

2. Loosen the purging screw slightly and allow the oil to drain until the loader lowers to the ground. Tighten the purging screw after the loader is on the ground.

Lowering the Boom

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Personal injury or death can result from the boom falling. Keep personnel away from the rear of the machine when lowering the boom.

Lowering the Boom with Electrical Power

If there is a loss of hydraulic power, and the machine meets the following conditions, perform the following procedure to lower the boom to the ground.

• Electrical power is available.

• There is not a break in a hydraulic line.

1. Place the hydraulic lockout switch in the UNLOCK position.

2. Turn the engine start switch key to the ON position and crank for five seconds.

3. Leave the key in the ON position.

4. Slowly tap the joystick control for the boom into the DOWN position in order to lower the boom to the ground.

Lowering the Boom without Electrical Power

If there is not electrical power and there is not a break in a hydraulic line, perform the following procedure to lower the boom to the ground.

Note: Two people are needed in order to manually lower the loader. One person should be used in order to ensure that all personnel are clear of the machine while the loader is being lowered.

1. Ensure that the parking brake is engaged.

2. Locate the backhoe control valve underneath the rear of the machine.

3. Remove the pilot control line and remove the fitting from the bottom of the boom control valve.

4. Fully install the 308-4547 Valve Adjuster.

5. Turn in by hand the screw in the center of the 308-4547 Valve Adjuster, until it contacts the spool.

6. Use a suitable tool in order to turn the center of the 308-4547 Valve Adjuster fully in.
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   Illustration 4	g02047755
   Boom Lock Valve

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   Illustration 5	g01207006

7. Remove the tamperproof cap on the boom lock valve.
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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 product. 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 Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Caterpillar products. Dispose of all fluids according to local regulations and mandates.

8. Loosen the locknut. Slowly, turn the screw clockwise by 90 degrees until the boom begins to lower. This will open the lock valve which will allow the boom to lower. Allow the boom to lower slowly in order to ensure the boom is under control.

9. Once the boom has been lowered, return the screw to the original position. Tighten the locknut.

10. When the boom has been fully lowered, remove the service tool and reconnect the pilot control line to the valve section.

Lowering the Boom with a Hydraulic Component Failure

If a hydraulic component has failed, perform the following procedure to lower the boom to the ground.

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Illustration 6	g02047755
Boom Lock Valve

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Illustration 7	g01207006

1. Remove the tamperproof cap on the boom lock valve.
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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 product. 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 Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Caterpillar products. Dispose of all fluids according to local regulations and mandates.

2. Loosen the locknut. Slowly, turn the screw clockwise by 90 degrees until the boom begins to lower. This will open the lock valve which will allow the boom to lower. Allow the boom to lower slowly in order to ensure the boom is under control.

3. Once the boom has been lowered, return the screw to the original position. Tighten the locknut.