ELBOW 1W0513 - Caterpillar

Sudden movement or accidental starting of the machine can cause personal injury or death to persons on or near the machine.To prevent personal injury or death, perform the following:Park the machine on a smooth, level surface.Lower the work tool to the ground and engage the parking brake.Stop the engine and remove the key.Block the wheels and install the steering frame lock.
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.
Specifications
Table 1
Pilot Pressure - High Idle
3,450 350 kPa (500 50 psi)
Introduction
There are two pilot systems that are generated from the fan/brake valve in the hydraulic service center.
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 Check 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.
Install the steering frame lock.Test Procedure
Illustration 2 g06044532
Pressure taps located on the left inside wall of the articulated hitch on the front differential lock valve.
(1) Implement/ Redundant Steering Pilot Supply Pressure Tap
(2) Implement Load Sense Pressure Tap
Install tooling (A) to test port (1).
Start the engine and warm up the hydraulics if necessary. The hydraulic oil temperature should be at least 60° C (140° F).
Increase the engine speed to high idle.
Observe the pilot pressure on tooling (A), the pressure should be 3500 345 kPa (508 50 psi).
Lower the engine speed to low idle.
Stop the engine.
Remove tooling (A).Check complete.Adjustment Procedure
Illustration 3 g06044833
Brake/Fan valve located in hydraulic service center on the right side of machine
(A) Fan/brake valve
(3) Pressure reducing valve (PRV)Locate the implement/redundant steering pilot pressure reducing valve (PRV) (3) on the side of the fan/brake valve (A) in the service center. Use a hex wrench to loosen the lock-nut and an internal hex wrench to adjust the pilot pressure.
To increase pressure
Hold the adjustment screw with the internal hex wrench and loosen the lock-nut
Turn the adjustment screw inward. A quarter or half turn is often enough to reach the desired setting.
Holding the adjustment