RING 6P8258 - Caterpillar

Escaping fluid under pressure, even a pinhole size leak, can penetrate body tissue, causing 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.
Personal injury can result from hydraulic oil pressure and hot oil.Hydraulic oil pressure can remain in the hydraulic system after the engine has been stopped. Serious injury can be caused if this pressure is not released before any service is done on the hydraulic system.Make sure all of the attachments have been lowered, oil is cool before removing any components or lines. Remove the oil filler cap only when the engine is stopped, and the filler cap is cool enough to touch with your bare hand.
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.
Introduction
The following test procedure will check the pressure of the oil that returns from the hydraulic oil cooler.Required Tools
Illustration 1 g01089423
Tooling (K) Use the tools in Table 1 to complete the following test procedure.
Table 1
Required Tools (Pressure Gauges)    
Tool    Item    Part Number    Description    Qty    
A     A1     6V-3989     Fitting (Test)     2    
A2 8T-0855     Pressure Gauge     2    
A3 177-7861     Hose As     2    
A4 6V-4143     Coupler     4    
        143-4065     Pressure Sensor
0 to 6895 kPa (0 to 1000 psi)     1    Test Procedure
A pressure gauge is used in the following test procedure:
Illustration 2 g03097017
Pressure tap location for the hydraulic cooler return oil
Warm the oil to a minimum temperature of 60°C (140°F).ReferenceSee Systems Operation/Testing and Adjusting, "General Testing and Adjusting Information" for information on warming the oil.
Connect Tooling (A) to test port (1) .
Start the engine. Run the engine at high idle.
Make sure that the temperature of the hydraulic oil is at least 60°C (140°F). Record the pressure of the hydraulic oil that is coming from the hydraulic oil cooler. The pressure of the oil that is returning from the hydraulic oil cooler should be 520 kPa (75 psi).
Remove Tooling (A) from test port (1) .
Stop the engine.