349F and 352F Excavators Hydraulic System Cylinder Drift - Check

Table 1
"Cylinder Drift - Check (Empty Bucket)"
Item	Cylinder Position	New	Service Limit	Actual
Boom Cylinder	Extended	6.0 mm (0.24 inch) or less	24.0 mm (0.94 inch) or less
Stick Cylinder	Retracted	10.0 mm (0.39 inch) or less	25.0 mm (0.98 inch) or less
Stick Cylinder	Extended	25.0 mm (0.98 inch) or less	40.0 mm (1.57 inch) or less
Bucket Cylinder	Extended	10.0 mm (0.39 inch) or less	25.0 mm (0.98 inch) or less
Bucket Cylinder	Retracted	20.0 mm (0.79 inch) or less	35.0 mm (1.38 inch) or less

Introduction

The performance level of the cylinder, the cylinder seals, and the overload relief valves for the implements can be determined with the following procedure.

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, "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".

Required Tools

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Table 2
Required Tools
Description	Qty
Measuring Tape	1
Stopwatch	1

Test Procedure

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Illustration 1	g00298378

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

Boom Cylinder Head End, Stick Cylinder Rod End, and Bucket Cylinder Head End

Fully extend the bucket cylinder.
Fully retract the stick cylinder.
Extend the stick cylinder rod 70 mm (2.8 inch) from the fully retracted position.
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Illustration 2 g01402004
Raise the boom until the stick to bucket pin is the same height as the boom foot pin. Refer to Illustration 2.
Measure the length of each cylinder from cylinder pin to cylinder pin.
Stop the engine.
Leave the machine in this position for 5 minutes. Measure the length of each cylinder from cylinder pin to cylinder pin for drift.

Stick Cylinder Head End

Start the engine.
Fully extend the bucket cylinder.
Fully extend the stick cylinder.
Retract the stick cylinder rod 60 mm (2.4 inch) from the fully extended position.
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Illustration 3 g01401745
Raise the boom until the stick to bucket pin is 600.0 mm (23.6 inch) high from ground level. Refer to Illustration 3.
Measure the stick cylinders length from cylinder pin to cylinder pin.
Stop the engine.
Leave the machine in this position for 5 minutes. Measure the stick cylinders length from cylinder pin to cylinder pin for drift.

Bucket Cylinder Rod End

Start the engine.
Fully retract the bucket cylinder.
Fully retract the stick cylinder.
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Illustration 4 g01401747
Raise the boom until the stick to bucket pin is 600.0 mm ( 23.6 inch) high from ground level. Refer to Illustration 4.
Measure the bucket cylinders length from cylinder pin to cylinder pin.
Stop the engine.
Leave the machine in this position for 5 minutes. Measure the bucket cylinders length from cylinder pin to cylinder pin for drift.