GUARD ASSEM. (belt) 8N5789 - Caterpillar

Procedure for Pressure Release
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.
Cylinders equipped with lock valves can remain pressurized for very long periods of time, even with the hoses removed.Failure to relieve pressure before removing a lock valve or disassembling a cylinder can result in personal injury or death.Ensure all pressure is relieved before removing a lock valve or disassembling a cylinder.
Note: Cleanliness is an important factor. Before you begin this procedure, make sure that you thoroughly clean the exterior of the component. This will help to prevent dirt from entering the internal mechanism. Precision components can be damaged by contaminants or by dirt.
Release the hydraulic system pressure. Refer to Disassembly and Assembly, "Hydraulic System Pressure - Release".
Illustration 1 g01374217
Illustration 2 g01374243
Remove cover (1) from the top of the hydraulic tank. Slowly loosen plug (2) in order to release pressure in the hydraulic tank. Leave plug (2) loose for a minimum of 45 seconds in order to release any pressure that may be present in the return line. After the pressure is relieved, remove plug (2).
Illustration 3 g01374531
(4) Boom cylinder
Illustration 4 g01374064
Slowly loosen valve (5) on boom lowering control valve (3) in order to release residual pressure in boom cylinder (4).
Illustration 5 g01374243
Illustration 6 g01374064
After the pressure has been released, tighten plug (2) to a torque of 68 7 N m (50 5 lb ft). Tighten valve (5) on boom lowering control valve (3) to a torque of 47 9 N m (34.6 6.6 lb ft).