RING 6P8264 - 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 charge oil that is being delivered from a modulating valve (transmission) to a transmission clutch. There are nine individual modulating valves that control the nine transmission clutches. The modulating valves (transmission) are modulated. The modulation of these valves can be adjusted.Required Tools
Illustration 1 g01089423
Tooling (A) 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
Pressure gauges are used in the following test procedure.
Illustration 2 g02731405
Transmission ClutchesThe designated letters are used to correlate a modulating valve to the corresponding transmission clutch, as shown.
Illustration 3 g02731409
Modulating Valves (Transmission)Each modulating valve has a designated letter, as shown. The letters have been cast into the transmission housing.Log the clutch pressures in Table 2. There are always two clutches that are engaged for each gear selection. NEUTRAL position only uses one clutch. See Table 2 in order to determine the clutches that are engaged for each gear selection.
Table 2
Checklist for Transmission Clutch Pressures    
Gear    Clutch or Valve    Pressure Measurement    Clutch or Valve    Pressure Measurement    
Fourth gear (reverse)     A         J        
Third gear (reverse)     A         H        
Second gear (reverse)     A         B        
First gear (reverse)     A         G