CABLE AS 4V9546 - Caterpillar

ReferenceFor additional information on the operation of the hydraulic system, refer to Specifications for the machine that is being serviced.Specifications
The secondary steering pump is a gear type pump.For the pump flow test, use SAE 10W oil that is at 65°C (150°F).
Table 1
Gear Pump (Secondary Steering)    
Pump Flow     Output     Pressure     Pump Speed     Engine Speed    
Full Speed    
166 L/min (44 US gpm)    
690 kPa (100 psi)     2000 rpm     2000 rpm    
149 L/min (40 US gpm)
6900 kPa (1000 psi)     2000 rpm     2000 rpm    
Half Speed    
83 L/min (22 US gpm)    
690 kPa (100 psi)     1000 rpm     1000 rpm    
75 L/min (20 US gpm)
6900 kPa (1000 psi)     1000 rpm     1000 rpm    
Illustration 1 g03071396
Secondary steering pumpIntroduction
This test is designed to determine whether a pump is operating within design parameters. This test should be performed only if all cylinder cycle times are too slow.For any pump test, the pump flow at 690 kPa (100 psi) will be larger than the pump flow at 6900 kPa (1000 psi) if the pump is operating at the same rpm. The pump flow is measured in L/min (US gpm).The difference between the pump flow of two operating pressures is the flow loss.Note: The values in the examples are not set values for any specific pump or for any specific pump condition. See the Specification for the pump flow of a new pump at 690 kPa (100 psi) and at 6900 kPa (1000 psi).
Table 2
Method of determining flow loss    
    Pump flow at
690 kPa (100 psi)        
−     Pump flow at
6900 kPa (1000 psi)        
    Flow loss        
Table 3
Example of determining flow loss    
   
217.6 L/min (57.5 US gpm)        
−    
196.8 L/min (52.0 US gpm)        
   
20.8 L/min (5.5 US gpm)        Flow loss that is expressed as a percentage of pump flow is used as a measure of pump performance.
Table 4
Method of determining percent of flow loss    
Flow loss (L/min or US gpm)     ×     100     =     Percent of flow loss    
Pump flow at
690 kPa (100 psi)    
Table 5
Example of determining percent of flow loss    
20.8 L (5.5 US gal)     ×     100     =     9.5%    
217.6 L/min (57.5 US gpm)    Test Preparation
Illustration 2 g03075296
Steering frame lock installed (1) Steering frame lock
Install the steering frame lock (1). ReferenceRefer to Operation and Maintenance Manual, "Steering Frame Lock" for the machine being serviced.
Remove the secondary steering pump. Refer to Disassembly and Assembly, "Gear Pump (Secondary Steering) - Remove" for the machine being serviced.Test Procedure
Bench Test
If the test bench can be run at 6900 kPa (1000 psi) and at full pump rpm, use the formula in Table 6 to determine the percent of flow loss.If the test bench cannot be run at 6900 kPa (1000