308C CR Excavator Hydraulic System – Swing Speed and Swing Drift on a Slope – Check

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 g00298078
  1. Complete the following steps in order to measure the swing speed on a slope.
    1. Start the engine.
    1. Place the machine controls at the following settings: Engine speed dial “10” and Low idle switch OFF.
    1. Place the hydraulic activation control lever in the UNLOCKED position.
    1. Increase the hydraulic oil temperature to 55° ± 5°C (131° ± 9°F).
    1. The bucket should be empty.
    1. Position the machine on a slope of 12 degrees. Refer to Illustration 1.
    1. Position the implements at maximum reach and close the bucket. Position the bucket above the ground so that the bucket will not come in contact with any obstacles.

      Illustration 2 g00298079

    1. Position the upper structure at position (A). The upper structure should be at a 90 degree angle to the lower structure. Refer to Illustration 2.
    1. Measure the time that is required to swing the upper structure from position (A) to position (B) .
    1. Position the upper structure at position (C). The upper structure should be at a 90 degree angle to the lower structure.
    1. Measure the time that is required to swing the upper structure from position (C) to position (B).

      Table 2
      Swing Time (seconds)    
      Item     New     Rebuild     Service Limit    
      Right Swing     3.4 or less     3.9 or less     4.4 or less    
      Left Swing    

  1. Complete the following steps in order to measure the swing drift on a slope.

      Illustration 3 g00298079

    1. Position the upper structure at position (A). The upper structure should be at a 90 degree angle to the lower structure. Refer to Illustration 3.

      Illustration 4 g00293972

      (A) Upper frame

      (B) Undercarriage frame

      (C) Marking

    1. To indicate the relationship of the two positions, put a mark (C) on the inner race and the outer race of the swing bearing. Refer to Illustration 4.
    1. Stop the engine.
    1. Leave the machine in this position for three minutes. Measure the swing drift on the circumference of the swing bearing.
    1. Start the engine.
    1. Position the upper structure at position (C). The upper structure should be at a 90 degree angle to the lower structure. Refer to Illustration 3.
    1. Repeat Steps 2.b through 2.d.
Table 3
Swing Drift mm (inch)    
Item     New     Rebuild     Service Limit    
Right Swing     0     0     0    
Left Swing