BODY-SELECTOR 7G3472 - Caterpillar

Table 1
Tools Needed    
Part Number     Description     Quantity    
8T-5320     Hydraulic Test Group     1    
198-4240     Digital Pressure Indicator     1    
1U-5796     Pressure Differential Gauge Group (1)     1    
( 1 ) Optional
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.
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 Tools and Shop Products Guide" for tools and supplies suitable to collect and contain fluids on Caterpillar products.Dispose of all fluids according to local regulations and mandates.
Preparation for Testing
Purge the air from the load sensing system.Reference: Refer to Testing and Adjusting, "Load Sensing System - Purge" for more information.
Ensure that the hydraulic oil in the system is at normal operating temperature. Park the machine on a smooth, level surface.
Fully lower the machine. Lower the work tool to the ground. Place the operating mode switch in the NEUTRAL position. Place the boom switch in the OFF position.
Install the steering frame lock. Block the wheels. Install the swing lock pins. Stop the engine.Testing Procedure
Illustration 1 g00673378
End View of the Implement Control Valve (1) Signal pressure tap. (2) Pump pressure tap.
Connect the low pressure port of the digital pressure indicator to pressure tap (1). Connect the high pressure port of the digital pressure indicator to pressure tap (2) .
Start the engine. Increase the engine speed to approximately 1500 rpm. Turn the boom switch to the ON position.
With the harvester head approximately 2 m (6 ft) from the front of the machine, raise the boom at half of maximum speed.
The margin pressure will be indicated on the digital gauge. If two pressure gauges are used, the margin pressure is the difference between the pressure readings on the two pressure gauges. The margin pressure should be approximately 3500 kPa (500 psi). If the margin pressure is out of range then perform steps 1 through 3 under "Adjusting Procedure".
Lower the boom and stick to the ground.
Turn the boom activation switch to the OFF position.
Stop the engine.
Disconnect the digital pressure indicator.Adjusting Procedure
Illustration 2 g00486211
View of the Implement Pump (3) Locknut. (4) Adjustment screw for margin pressure.
To adjust the margin pressure, loosen locknut (3). Turn adjustment screw (4) clockwise in order to increase the margin pressure. Turn adjustment screw (4) counterclockwise in order to decrease the margin pressure. Adjust the pressure until the differential pressure gauge indicates approximately 3500 kPa (500 psi).
Tighten locknut (3). Raise the boom again in order to confirm the new pressure