H35D S, H45D S, H55D S and H65D S Hydraulic Hammers Caterpillar

Testing the Hydraulic Accumulator (Low Pressure)

Note: Residual hydraulic pressure should be relieved prior to checking the accumulator charge. Failure to relieve the pressure could result in an inaccurate pressure reading on the pressure gauge.

Reference: Testing and Adjusting, "Work Tool Preparation for Troubleshooting"

Illustration 1	g01285191
(X) Accumulator (low pressure (1) Plug (2) Plug

Illustration 2	g01167053
(X) Accumulator (low pressure (1) Plug (2) Plug

1. Remove plug (1) from the housing of the hammer.

2. Use a hex driver in order to remove outer plug (2) from port (X) of the accumulator.
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   Illustration 3	g01285192

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   Illustration 4	g01167093

3. Screw 229-3440 Charging Adapter Gp (K) into port (X) of the accumulator. Turn the charging tool at point (C) in order to install the charging tool. Tighten the charging tool to 60 ± 10 N·m (44 ± 7 lb ft) in order to properly seat the charging tool.

   Note: The 229-3442 Pin of 229-3440 Charging Adapter Group (K) should be properly inserted into the hex of the plug that is located within port (X).

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   Illustration 5	g01285193

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   Illustration 6	g01167113

4. Connect the 121-6583 Accumulator Charging Group (H) to 229-3440 Charging Adapter Gp (K).

5. Close purge valve (5) on 121-6583 Accumulator Charging Group (H).
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   Illustration 7	g00941279

6. Connect one end of 9U-6739 Hose Assembly (L) to 121-6583 Accumulator Charging Group (H).

7. Connect the other end of 9U-6739 Hose Assembly (L) to 175-5507 Nitrogen Charging Group (J).

   Note: Before opening the accumulator fill plug you must pre-charge the 121-6583 Accumulator Charging Group (H) to the recommended charge specification of the hydraulic accumulator.

8. In order to pre-charge the 121-6583 Accumulator Charging Group (H) ensure that the accumulator fill plug is closed.

9. Carefully open the valve on the nitrogen gas cylinder. Set the regulator of the 175-5507 Nitrogen Charging Group (J) to the recommended specification of the accumulator that is being filled or checked. Refer to table 3.

10. Close the valve on the nitrogen gas cylinder.

11. Check the pressure on the gauge of the charging tool. Ensure that the pressure is correct for the recommended specification of the accumulator that is being filled or checked.

12. In order to unscrew the plug, turn the hex driver at point (B) until the gas pressure in the high pressure accumumulator can be read on the gauge of the charging tool. Do not exceed 2.75 complete turns in order to avoid the plug backing out and hitting the charging tool..

13. Check the pressure on the gauge of the charging tool.

14. Add the necessary amount of nitrogen in order to achieve the proper level of charge. Refer to "Charging the Hydraulic Accumulator (Low Pressure)".

Charging the Hydraulic Accumulator (Low Pressure)

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Illustration 8	g01285191
(X) Accumulator (high pressure) (1) Plug (2) Plug

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Illustration 9	g01167053
(X) Accumulator (high pressure) (1) Plug (2) Plug

1. Remove plug (1) from the housing of the hammer.

2. Use a hex driver in order to remove outer plug (2) from port (A) of the accumulator.
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   Illustration 10	g01285192

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   Illustration 11	g01167093

3. Screw 229-3440 Charging Adapter Group (K) into port (A) of the accumulator. Turn the charging tool at point (C) in order to install the charging tool. Tighten the charging tool to 60 ± 10 N·m (44 ± 7 lb ft) in order to properly seat the charging tool.

   Note: The 229-3442 Pin of 229-3440 Charging Adapter Gp (K) should be properly inserted into the hex of the plug that is located within port (X).

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   Illustration 12	g01285193

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   Illustration 13	g01167113

4. Connect 121-6583 Accumulator Charging Group (H) to 229-3440 Charging Adapter Group (K). The following components are included in the 121-6583 Accumulator Charging Group:

   • 7Q-8499 Pin

   • 7Q-8498 Adapter

   • 3K-0360 O-Ring Seal

   • 9U-6740 Accumulator Charging Group

   • 8T-0856 Pressure Gauge

5. Close purge valve (5) on 121-6583 Accumulator Charging Group (H).
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   Illustration 14	g00941279

6. Connect one end of 9U-6739 Hose Assembly (L) to 121-6583 Accumulator Charging Group (H).

7. Connect the other end of 9U-6739 Hose Assembly (L) to 175-5507 Nitrogen Charging Group (J).

   Note: Before opening the accumulator fill plug you must pre-charge the 121-6583 Accumulator Charging Group (H) to the recommended charge specification of the hydraulic accumulator.

8. In order to pre-charge the 121-6583 Accumulator Charging Group (H) ensure that the accumulator fill plug is closed.

9. Carefully open the valve on the nitrogen gas cylinder. Set the regulator of the 175-5507 Nitrogen Charging Group (J) to the recommended specification of the accumulator that is being filled or checked. Refer to table 3.

10. Close the valve on the nitrogen gas cylinder.

11. Check the pressure on the gauge of the charging tool. Ensure that the pressure is correct for the recommended specification of the accumulator that is being filled or checked.

12. In order to unscrew the plug, turn the hex driver at point (B) until the gas pressure in the high pressure accumulator can be read on the gauge of the charging tool. Do not exceed 2.75 complete turns in order to avoid the plug from backing out and hitting the charging tool.

13. Check the pressure on the gauge of the charging tool. Add the appropriate amount of nitrogen in order to achieve the proper level of charge.

    Note: Before you open the valve on the nitrogen gas cylinder, you must ensure that the adjustment screw on the regulator for the 175-5507 Nitrogen Charging Group (J) is completely backed out.

14. Carefully open the valve on the nitrogen gas cylinder. Set the regulator of 175-5507 Nitrogen Charging Group (J) to the preliminary pressure of 50 kPa (7 psi) more than the target gas pressure. Refer to table 3 .

15. Close the valve on the nitrogen gas cylinder.

16. Wait for ten minutes in order to allow the nitrogen gas pressure to stabilize inside the accumulator.
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    Table 3

    Temperature of the Gas	Gas Pressure
    0 °C (32 °F)	1850 ± 100 kPa (269 ± 15 psi)
    20 °C (68 °F)	2000 ± 100 kPa (291 ± 15 psi)
    40 °C (104 °F)	2100 ± 100 kPa (305 ± 15 psi)
    60 °C (140 °F)	2250 ± 100 kPa (327 ± 15 psi)

17. Adjust the accumulator pressure on the pressure gauge to the final pressure. Refer to Table 3 for determining the correct gas pressure at the given temperature of the gas.

18. After the correct pressure for the accumulator has been achieved, use socket drive (B) on the charging tool in order to tighten the plug within port (X) to a torque of 16 + 1.5 N·m (12 + 1 lb ft or 142 + 13 in ft).

    Note: Do not overtighten the plug. Failure of the hex in the plug may result.

19. Open purge valve (5) on 121-6583 Accumulator Charging Group (H) in order to relieve 9U-6739 Hose Assembly (L) of nitrogen.

20. Disconnect 9U-6739 Hose Assembly (L) from 121-6583 Accumulator Charging Group (H).

21. Remove 121-6583 Accumulator Charging Group (H) from 229-3440 Charging Adapter Group (K).

22. Remove 229-3440 Charging Adapter Group (K) from the accumulator.

23. Make sure that the O-ring seal on plug (2) is in good condition. Install plug (2). Tighten plug (2) to a torque of 70 + 7 N·m (52 + 5 lb ft).