Adjustment Procedure for the Extendable Stick Wear Pads{6533} Caterpillar

Backhoe Loader:

416E (S/N: LMS1-UP; SHA1-UP; BWC1-UP)

420E (S/N: DJL1-UP; DAN1-UP; PRA1-UP; PHC1-UP; HLS1-UP; KMW1-UP)

430E (S/N: MXB1-UP; SWC1-UP; SCD1-UP; RLN1-UP; DDT1-UP; EAT1-UP)

Introduction

This Special Instruction explains the adjustment of the wear pads on the extendable stick. Do not begin the adjustment until you have read the information that is contained in this instruction.

Work safely. Most accidents that involve product operation, maintenance, and repair are caused by failure to observe basic safety rules or precautions. An accident can often be avoided by recognizing potentially hazardous situations before an accident occurs. A person must be alert to potential hazards. This person should also have the necessary training, skills, and tools in order to perform these functions properly.

Safety precautions and warnings are provided in this instruction and on the product. If these hazard warnings are not heeded, bodily injury or death could occur to you or to other persons. Refer to the Operation and Maintenance Manual for your machine.

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Hydraulic oil pressure can remain in the hydraulic systems after the engine and pump have been stopped. Serious injury can be caused if this pressure is not released before any service is done on the hydraulic systems. To prevent possible injury, refer to the section, Testing and Adjusting, "Hydraulic System Pressure - Release" before any fitting, hose or component is loosened, tightened, removed or adjusted. When possible, the bucket or attachment must always be lowered to the ground before service is started. When it is necessary for the boom to be in the raised position while tests or adjustments are done, be sure that the boom, stick and bucket or attachment have correct support. The swing lock (if equipped) must be engaged before service is started. Always move the machine to a location away from the travel of other machines. Be sure that other personnel are not near the machine when the engine is running and tests or adjustments are being made.

Required Tools

Inspect the Gap of the Wear Pads

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Illustration 1	g01409830

1. Position the machine. Refer to Illustration 1.

2. Raise the rear of the backhoe so that tires are off 25.4 mm (1.00 inch) of the ground.

3. Fully extend the stick. Then, retract the stick 76.2 mm to 101.6 mm (3 inch to 4 inch).

4. Pull stick in and position the rear bucket so that the bottom of the bucket and the bucket teeth are flat on the ground.

5. Fully extend the extendable stick. Lift the stabilizers off the ground.

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Illustration 2	g01285949

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Illustration 3	g01409837

6. Use a feeler gauge to measure the gap between the top of the wedge and the bottom surface of the inner stick. This gap needs to be between 0.5 mm (0.02 inch) and 1.0 mm (0.04 inch) at all points.

7. Check for clearance on the upper wear pad. If the gap between the upper wear pad and the bottom surface of the inner stick is less than 0.5 mm (0.02 inch) proceed to Step 8, or more than 1 mm (0.04 inch) proceed to Step 9.

8. If the gap is less than 0.5 mm (0.02 inch) perform the following steps:
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   Illustration 4	g01206164
   (1) 222-5171 Setscrew (2) 8T-4910 Bolts

   1. Retract the stick to the halfway position.

   2. Loosen the bolts (2) that secure the upper wear pad in place.

      Note: Do not loosen the two bolts that are under the setscrew.

   3. Loosen the setscrew (1) by one to two turns.

   4. Fully extend the stick. The upper wear pad should slide back to the stop.

   5. Return the machine to the previous setup. Refer to Step 1.

   6. Turn the set screw counterclockwise in order to increase the gap.

   7. After you set the clearance, tighten bolts (2) in order to secure the upper wear pad.

   8. Measure the gap and make any needed adjustments.

   9. If the gap is correct, apply 154-9731 Thread Lock Compound to both bolts (2) .

   10. Torque bolts (2) to 100 ± 20 N·m (74 ± 15 lb ft).

   11. Proceed to Step 10.

9. If the gap is more than 1 mm (0.04 inch) perform the following steps:

   1. Loosen the bolts (2) that secure the upper wear pad in place.

      Note: Do not loosen the two bolts that are under the setscrew.

   2. Turn the set screw (1) clockwise in order to decrease the gap.

   3. After you set the clearance, tighten bolts (2) in order to secure the upper wear pad.

   4. Measure the gap and make any needed adjustments.

   5. If the gap is correct, apply 154-9731 Thread Lock Compound to both bolts (2) .

   6. Torque bolts (2) to 100 ± 20 N·m (74 ± 15 lb ft).

   7. Proceed to Step 10.

10. Check extension of the stick after adjusting the upper wear pad.

    1. Set the stick horizontally to the ground.

    2. Extend the stick and retract the stick in order to check for any vibrations.

    3. If no vibration is evident, continue to ""Inspect the Gap of the Lower Wear Pads" ".

    4. If the vibration is evident, adjust the upper wear pad to the maximum gap of 1 mm (0.04 inch). If the vibration continues contact the DSN.

       Note: A small amount of vertical movement of the outer slider is acceptable with a gap of 1 mm (0.04 inch).

Inspect the Gap of the Lower Wear Pads

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Illustration 5	g01285951

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Illustration 6	g01409844

1. Remove the access panel on the nose of the extendable stick.

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Illustration 7	g01409845

2. Position the machine. Refer to Illustration 7.

3. Fully retract the extendable stick in order to allow access through the nose of the stick. Slightly lift the rear of the machine.

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Illustration 8	g01409846

4. Remove the rubber caps (A). Then, use a metric ruler to measure the gaps between the top of the flat wear pad (B) and the inside surface of the outer stick.

5. Check for clearance on the lower wear pad. If the gap between the lower wear pad and the bottom surface of the outer stick is less than 0.5 mm (0.02 inch) proceed to Step 6, or more than 1 mm (0.04 inch) proceed to Step 7.

6. If the gap is less than 0.5 mm (0.02 inch), perform the following steps:
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   Illustration 9	g01288003
   (3) 8T-4910 Bolts (4) 222-5171 Setscrew

   1. Loosen the two bolts (3) that secure the lower wear pad in place.

      Note: Do not loosen the two bolts that are under the setscrew.

   2. Loosen the setscrew (4) by one to two turns.

   3. Slide the stick out 25 mm (1 inch) to 75 mm (3 inch).

      Note: The lower wear pad should return against the set screw. This will create a gap between the lower wear pad and the outer extendable stick.

      Note: Ensure that the wear pad is pulled back against the set screw. Tighten the bolts. Ensure that you can access the bolts after the stick has been extended by a few inches.

   4. Return the machine to the previous setup. Refer to Step 2.

   5. Measure the gap and make any needed adjustments.

   6. If the gap is correct, apply 154-9731 Thread Lock Compound to both bolts (1) .

   7. Torque the bolts (3) to 100 ± 20 N·m (74 ± 15 lb ft).

   8. Proceed to Step 11.

7. If the gap is more than 1 mm (0.4 inch), perform the following steps:

   1. Loosen the two bolts (3) that secure the lower wear pad in place.

      Note: Do not loosen the two bolts that are under the setscrew.

   2. Turn the set screw (4) clockwise in order to decrease the gap.

   3. Measure the gap and make any needed adjustments.

   4. If the gap is correct, apply 154-9731 Thread Lock Compound to both bolts (1) .

   5. Torque the bolts (3) to 100 ± 20 N·m (74 ± 15 lb ft).

   6. Proceed to Step 8.

8. Check extension of the stick after adjusting the lower wear pad.

   1. Set the stick horizontally to the ground.

   2. Extend the stick and retract the stick in order to check for any vibrations.

   3. If no vibration is evident, continue to the adjustment of the side wear pads. Refer to Step 1.

   4. If vibration is evident, adjust the lower wear pad to the maximum gap of 1 mm (0.04 inch). If the vibration continues, contact the DSN.

      Note: A small amount of vertical movement of the outer slider is acceptable with a gap of 1 mm (0.04 inch).

   5. Proceed to Step 1.

Adjustment of the Side Wear Pads

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Illustration 10	g01410293

1. Position the machine. Refer to Illustration 10.

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Illustration 11	g01283762

2. Raise the rear of the backhoe and make sure that the boom nose is level with the ground. Fully extend the stick and place the curled bucket slightly off the ground.

3. Check for free play between the side wear pads and the inner section of the stick.

4. Check each side wear pad with the outer slider in the following positions.
   • Extended 50.8 mm (2 inch) to 76.2 mm (3 inch)

   • Half extended

   • Fully extended

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Illustration 12	g01410355
(C) 0.25 mm (0.0098 inch) (D) No gap

5. Use a 0.25 mm (0.0098 inch) feeler gauge to check each side wear pad. One side should have no gap between the inner slider and the face of the pad (D). The other side should have a 0.25 mm (0.0098 inch) or less gap (C). See Illustration 12.

6. Ensure that a 0.25 mm (0.0098 inch) gap is present at the widest part of the three checked positions. This will be the position of the smallest gap between the inner slider and side wear pad. Setting the 0.25 mm (0.0098 inch) gap at a narrow point of the inner slider may allow vibrating as the wear pads travel over the wider points of the slider.

7. If adjustment is required, perform the following steps:
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   Illustration 13	g01288005
   (5) 284-3615 Hex Socket Screws (6) 233-5165 Plate

   1. Remove the 4 hex socket screws (5) and the plate (6) .

   2. Apply an adequate number of shims in order to make the side lower wear pad flush with shims.

      Note: The amount of shims should be equal on both sides within 0.5 mm (0.02 inch). The top side pad and bottom side pad do not need to have an equal number of shims.

   3. Reassemble the cover (6) and torque the hex socket screws (5) to 50 ± 10 N·m (37 ± 7 lb ft).

   4. Repeat Steps 7.a through 7.c for the remaining three additional side pads.

   5. Proceed to Step 8.

8. Check extension of the stick after adjusting the side wear pads.

   1. Set the stick horizontally to the ground.

   2. Extend the stick and retract the stick in order to check for any vibrations.

   3. If adjustment is too tight, then add a 0.5 mm (0.02 inch) shim to one of the side pads and recheck the adjustment.

      Note: Choose a pad with the heaviest wear marks.

   4. If adjustment is still too tight, then add a 0.5 mm (0.02 inch) shim to the corresponding pad on the other side and recheck the adjustment.

   5. If adjustment continues to be too tight, then add a 0.5 mm (0.02 inch) shim to the remaining wear pads.

      Note: Recheck for vibration before the addition of each shim. Do not exceed 0.5 mm (0.02 inch) of additional shimming at all four pads.

   6. If the stick continues to vibrate, contact the DSN.