321C CR Excavator Hydraulic System Caterpillar

Note: The engine speed and/or the machine configuration that is used during this test can affect the results of this test. Refer to Testing and Adjusting, "Engine Performance - Test" for the engine speed that was used for this test. Refer to Testing and Adjusting, "Operational Checks" for the machine configurations that were used for this test.

Note: The relief valve pressure settings must be set to the relief valve pressure specification before performing this operational check. Refer to Testing and Adjusting, "Specifications".

Table 1

Required Tools
Part Number	Description	Qty
5P-3277	Measuring Tape	1
	Stopwatch	1

Illustration 1	g00298378

1. Position the machine on level ground. Refer to Illustration 1.

2. Load the bucket.

   Weight of bucket load

   321C CR ... 1050 kg (2310 lb)

   321C LCR ... 1200 kg (2650 lb)

3. Raise the boom until the top stick pin is the same height as the boom foot pin.

4. Fully extend the bucket cylinder.

5. Fully retract the stick cylinder.

6. Extend the stick cylinder rod 70 mm (2.8 inch) from the fully retracted position.

7. Measure each cylinder's length from cylinder pin to cylinder pin.

8. Stop the engine.

9. Leave the machine in this position for three minutes. Measure each cylinder's length from cylinder pin to cylinder pin for drift.

Table 2

Cylinder Drift (Loaded Bucket)
New Boom Cylinder	New Stick Cylinder	New Bucket Cylinder
6.0 mm (0.24 inch) or less	12.0 mm (0.47 inch) or less	18.0 mm (0.71 inch) or less