JOINT 9S1724 - Caterpillar

Introduction
The implement system pilot pressure is generated by a pressure reducing valve that is located in the front frame on the inside left frame rail.
The primary steering pilot system supplies pilot pressure to the steering system.
The implement/redundant steering pilot system supplies pilot pressure to the implement system and the steering system if the primary steering system fails.Required Tools
Illustration 1 g02571852
Tooling (A) 198-4240 Digital Pressure Indicator Gp
Table 2
Required Tools
Tool Item Qty Part Number Description
A 198-4240 Digital Pressure Indicator Gp
A1 1 198-4234 Digital Indicator
A2 1 198-4239 Pressure Sensor Gp
41,368 kPa (6,000 psi)
A3 1 198-4236 Adapter Cable As Machine Preparation
Move the machine to a smooth, horizontal location that is away from operating machines and away from personnel.
Place the transmission direction in the NEUTRAL position.
Engage the parking brake.
Lower the work tool to the ground.
Stop the engine.
Relieve the pressure in the hydraulic system.Reference: For more information about relieving the hydraulic pressure, refer to the Service Manual module Testing and Adjusting, "System Pressure - Release" for the machine that is being serviced.
Illustration 2 g06119446
View of articulation hitch from the right side of the machine
Install the steering frame lock.Pilot Oil Accumulator
The following procedure can be used in order to test the pilot oil accumulator. The pilot oil accumulator maintains pressure in the pilot hydraulic system. The accumulator allows you to lower the boom, and the work tools with a stopped engine.When you test or you charge the pilot oil accumulator, the pressure in the pilot hydraulic system must be released. The temperature of the nitrogen gas must also be taken into account. The pressure and volume of nitrogen gas varies with temperature.Operational Test for the Pilot Oil Accumulator
Illustration 3 g06121843
Location of the pressure tap for pilot pressure
(1) Test port for pilot pressure
(2) Pilot accumulator
Install tooling (A) onto pilot pressure test port (1).
Start the engine and run the engine at HIGH idle. The pressure gauge will read 3,515 345 kPa (510 50 psi).
Stop the engine. Turn the start switch to the ON position. Do not start the engine.
Move the implement control levers several times through the full range of travel. This process will relieve any pressure that may be present in the implement hydraulic system. Turn the