312C Excavator Machine Systems Bucket Cylinder

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, "Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Cat^® products. Dispose of all fluids according to local regulations and mandates.

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Illustration 1	g00357292
Typical example

Attach a suitable lifting device to bucket cylinder (4), and position the bucket cylinder on the stick. Make sure that the pin bores in the stick and in bucket cylinder (4) are aligned. Also, be sure that the grease fittings in the head end and in the rod end of the bucket cylinder are facing away from the stick.
Apply Tooling (A) on pin assembly (7). Temporarily install pin assembly (7). Do not remove the lifting device from bucket cylinder (4) at this time.
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Illustration 2 g00357375

Top view
Slide bucket cylinder (4) to one side until the bucket cylinder (4) makes contact with the stick. Measure the total clearance between bucket cylinder (4) and the stick at the pin bore. The total clearance of measurement (a) plus measurement (b) must not be more than 1.0 mm (0.04 inch). If the total clearance is less than 1.0 mm (0.04 inch), the addition of shims between the bucket cylinder and stick will not be required. If the total clearance is more than 1.0 mm (0.04 inch), the addition of shims between the bucket cylinder and the stick will be required.
If shims are required, remove pin assembly (7). Install the shims between the stick and bucket cylinder on the side opposite the retaining bolt for the pin assembly. Install the spacer and pin assembly (7). Install the washer and retaining bolt (6).
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Illustration 3 g00357377

Typical example
Lower the bucket cylinder between the link assemblies. Make sure that the bore in the bucket cylinder rod aligns with the bores in the link assemblies. Apply Tooling (A) on pin (2). Install pin (2). Install retaining bolt (1) and the two nuts. Rotate pin (2) until the pin is parallel with the link, as shown.
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Illustration 4 g00357378
Tighten the outside nut until the nut is 0.5 mm (0.02 inch) beyond the end of the retaining bolt, as shown. Tighten the inside nut against the outside nut.
Connect hose assemblies (5) to bucket cylinder (4). Refer to illustration 2.
Fill the hydraulic oil tank. Refer to Operation and Maintenance, "Lubricant Viscosisties and Refill Capacities". Lubricate the bucket cylinder support pins. Refer to Operation and Maintenance, "Bucket Linkage - Lubricate".
Start the machine, and run the machine at low idle speed. Remove wood block (3). Refer to illustration 3. Move the control lever for the bucket cylinder so that the cylinder rod extends to the halfway position. Retract the cylinder rod. Operate the cylinder in this manner for approximately ten cycles in order to remove the air from the hydraulic system. Recheck the oil level in the hydraulic oil tank. Refer to the Operation and Maintenance, "Hydraulic System Oil Level - Check".