MANIFOLD 7S6992 - Caterpillar

Personal injury or death can result from escaping fluid under pressure.Escaping fluid under pressure, even a very small pin-hole size leak, can penetrate body tissue and cause serious injury and possible death. If fluid is injected into your skin, it must be treated immediately by a doctor familiar with this type of injury.Always use a board or cardboard when checking for a leak.
Sudden movement of the machine or release of oil under pressure can cause injury to persons on or near the machine.In order to prevent possible injury, perform the following procedure before testing and adjusting any of the machine hydraulic systems.
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.
Park the machine on a smooth, level surface. Move away from other operating machines and away from personnel. Lower the implements to the ground. Stop the engine.
Permit only one operator on the machine. Keep all other personnel away from the machine or in sight of the operator.
Engage the parking brake. Put blocks in front of the wheels and behind the wheels.
Illustration 1 g00501895
Typical example of a steering frame lock
(1) Steering frame lock in the LOCKED position.
Install steering frame lock (1) in the LOCKED position so the machine can not articulate.
Depress the brake pedal repeatedly. This will relieve any pressure that may be present in the brake hydraulic system.Note: If the machine is equipped with electro-hydraulic controls, turn the engine start switch key to the ON position before performing step 6 and step 7. The engine start switch key must then be turned back to the OFF position before proceeding.
Move the implement control levers through the full range of travel. This will relieve any pressure that may be present in the implement hydraulic system. Place the lift control lever in the HOLD position. Place the tilt control lever in the HOLD position.
Turn the steering wheel several times in both directions in order to relieve the pressure in the steering system.
Illustration 2 g00495483
Typical example of a breaker relief valve.
(2) Breaker relief valve
In order to relieve all of the pressure in the hydraulic oil tank, press and hold down the plunger on breaker relief valve (2). The breaker relief valve is located on the top of the hydraulic oil tank.Note: If the machine is not equipped with a hydraulic tank breaker relief valve, the hydraulic tank cap may be removed slowly in order to relieve tank pressure.