784C, 785C and 785C HAA Off-Highway Truck/Tractors Hydraulic System Caterpillar

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Section A-A

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Section B-B

(1) 123-3848 Spring

Length under test force ... 48.00 mm (1.890 inch)

Test force ... 105.33 ± 5.25 N (23.68 ± 1.18 lb)

Free length after test ... 65.18 mm (2.566 inch)

Outside diameter ... 24.30 mm (0.957 inch)

(2) Fit the valve to the body so that there is a clearance of 0.025 to 0.036 mm (0.0010 to 0.0014 inch).

(3) 123-6777 Spring

Length under test force ... 23.01 mm (0.906 inch)

Test force ... 44.48 ± 2.20 N (10.00 ± 0.49 lb)

Free length after test ... 28.60 mm (1.126 inch)

Outside diameter ... 14.28 mm (0.562 inch)

(4) Fit the stem to the body so that there is a clearance of 0.018 to 0.028 mm (0.0007 to 0.0011 inch).

(5) High pressure relief valve setting ... 17225 + 700 - 0 kPa (2500 + 102 - 0 psi)

(6) Low pressure relief valve setting ... 3450 + 350 - 0 kPa (500 + 51 - 0 psi)

(7) 9J-3999 Spring

Length under test force ... 50.5 mm (1.99 inch)

Test force ... 308.7 ± 24.9 N (69.4 ± 5.6 lb)

Free length after test ... 59.2 mm (2.33 inch)

Outside diameter ... 14.53 mm (.572 inch)

(8) 129-6731 Spring

Length under test force ... 59.29 mm (2.334 inch)

Test force ... 0 ± 0 N (0 ± 0 lb)

Free length after test ... 59.29 mm (2.334 inch)

Outside diameter ... 14.50 mm (0.571 inch)

(9) 5J-2721 Shim

Quantity ... 3

Thickness ... 0.13 mm (0.005 inch)

Pressure change with one shim ... 65 kPa (9 psi)

Note: As required, the number of shims may be adjusted.

(10) 5J-2721 Shim

Quantity ... 10

Thickness ... 0.13 mm (0.005 inch)

Pressure change with one shim ... 13 kPa (2 psi)

Note: As required, the number of shims may be adjusted.

(11) 5J-2722 Shim

Quantity ... 2

Thickness ... 1.22 mm (0.048 inch)

Pressure change with one shim ... 610 kPa (88 psi)

Note: As required, the number of shims may be adjusted. Install these shims against the spring end.

(12) 5J-2722 Shim

Quantity ... 2

Thickness ... 1.22 mm (0.048 inch)

Pressure change with one shim ... 125 kPa (18 psi)

Note: As required, the number of shims may be adjusted. Install these shims against the spring end.

(13) Shrink the seats via temperature before inserting in the counterbore.