M313C, M315C, M316C, M318C and M322C Excavators and M318C and M322C Material Handlers Hydraulic System Caterpillar

Note: Reducing the pressure or oil flow below specifications results in less performance for all available medium pressure functions (hydraulic cab riser, joystick steering, and offset boom).

Table 1

Required Tools
Item	Part Number	Description	Qty
3	4C-9910	Portable Hydraulic Tester	1
4	6K-6307	O-Ring Seal	2
5	8C-9026	Adapter	2
6	7M-8485	O-Ring Seal	4
7	4C-6482	Fitting	2
8	4C-6481	Coupler	2
9	4C-8767	Coupling	2
10	5P-1010	Sleeve	4
11	5P-0201	Hose 3.5 m (11.5 ft)	2
12	7X-1452	Collet Stem	2
13	5K-9090	O-Ring Seal	2
14	8C-8762	Elbow	2
15	6V-8398	O-Ring Seal	2
16	114-9149	Fitting	2

Illustration 1	g00983986
Flow Meter Tool Layout (17) Line for rotator (18) Line for rotator

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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.

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Personal injury can result from hydraulic oil pressure and hot oil. Hydraulic oil pressure can remain in the hydraulic system after the engine has been stopped. Serious injury can be caused if this pressure is not released before any service is done on the hydraulic system. Make sure all of the work tools have been lowered to the ground, and the oil is cool before removing any components or lines. Remove the oil filler cap only when the engine is stopped, and the filler cap is cool enough to touch with your bare hand.

Adjustment of the Flow Rate

Note: The line relief pressure of the medium pressure function must be set to the correct specification before the flow rate can be tested.

1. Position the boom and stick for access to the end of the rotate lines.

2. Release the pressure in the hydraulic system. Refer to Testing and Adjusting, "Hydraulic System Pressure - Release".

3. Install a flow meter between the lines at the end of the boom or stick. Connect the pressure line for clockwise rotation to the inlet of the flow meter. Connect the return line to the outlet of the flow meter.

4. Start the engine.

5. Adjust the engine speed to HIGH IDLE by turning the engine speed dial to position 10.

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Illustration 2	g01259269
Soft Switch Panel (19) Automatic Engine Speed Control (AEC)

6. At the soft switch panel, disable AEC (19) by pushing down on the button. The indicator light will not be illuminated when the AEC is disabled. Refer to Testing and Adjusting, "Engine Preparation for Operation Checks" for engine rpm settings.

7. Increase the hydraulic oil temperature to 55° ± 5°C (131° ± 9°F).

8. Put the hydraulic activation control lever in the UNLOCKED position. Depress the switch for clockwise rotation.

9. Record the flow rate.

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Illustration 3	g01205708
Medium Pressure Control Valve (20) Flow reducing valve (21) Locknut (22) Adjustment screw

10. In order to adjust the flow for rotation, loosen locknut (21) on flow reducing valve (20). Turn adjustment screw (22) in order to adjust the flow rate. Adjust the flow to the manufacturer's specifications.

    Note: Turn the adjustment screw clockwise in order to reduce the flow. Turn the adjustment screw counterclockwise in order to increase the flow.

11. Disconnect the lines from the flow meter. Reconnect the lines to the rotator motor.

Adjustment of the Flow Rate (Optional test)

In some cases, the manufacturer of the work tool will specify the speed or RPM for the work tool that is being installed. If this specification is provided, use the following procedure:

1. Suspend the tool in the air.

2. Start the engine.

3. Adjust the engine speed to HIGH IDLE by turning the engine speed dial to position 10.

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Illustration 4	g01259269
Soft Switch Panel (19) Automatic Engine Speed Control (AEC)

4. At the soft switch panel, disable AEC (19) by pushing down on the button. The indicator light will not be illuminated when the AEC is disabled. Refer to Testing and Adjusting, "Engine Preparation for Operation Checks" for engine rpm settings.

5. Increase the hydraulic oil temperature to 55° ± 5°C (131° ± 9°F).

6. Put the hydraulic activation control lever in the UNLOCKED position. Depress the switch for clockwise rotation.

7. Record the RPM.

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Illustration 5	g01205708
Medium Pressure Control Valve (20) Flow reducing valve (21) Locknut (22) Adjustment screw

8. In order to adjust the RPM for rotation, loosen locknut (21) on flow reducing valve (20). Turn adjustment screw (22) in order to adjust the RPM. Adjust the RPM to the manufacturer's specifications.

   Note: Turn the adjustment screw clockwise in order to decrease the RPM. Turn the adjustment screw counterclockwise in order to increase the RPM.