Determining Total Flow Demand

1. Check flow setting for each function, independently. (See implement operator's manual, applications section, to determine correct motor flow settings.)

Examples of functions which may cause the pump to operate at high pressure:

  • Down pressure systems (drills, air seeders, disks)-usually can be considered to be zero flow demand after completion of raise or lower cycle (See Implement Connection Example 2 in this section.)
  • Auxiliary flow control valves (vacuum flow control)-Completely open implement flow control valve and adjust tractor flow rate to desired setting
  • Cylinder functions, where line or orifice restrictions control flow-Adjust tractor flow control to point where cycle time begins to increase
  • Auxiliary control valves (implement stack valves, row guidance)-Adjust tractor flow control to lowest setting resulting in correct operation

2. Determine total flow demand by adding flow requirements for each SCV using settings determined in Step 1. Include hitch and power beyond flow requirements, if applicable. (Refer to chart for correct settings.)

3. Determine if flow demand exceeds available pump flow. (Refer to chart for available pump flow):

  • Flow demand is less than available pump flow but there is performance concern. (See your John Deere Dealer.)
  • Flow demand exceeds pump flow:
    • Increase engine rpm if possible
    • Decrease flow setting on non critical functions
    • Convert implement open center valves to closed center operation, if possible

PUMP FLOW AVAILABLE
 
  Standard Pump Optional Pump
Engine rpm L/min gpm L/min gpm
         
800 48 12.7 60 15.9
1500 90 23.8 114 30.1
1700 102 26.9 129 34.1
1900 114 30.1 144 38.0
2100 126 33.3 159 42.0
         
 
SCV FLOW OUTPUT (Approximate) a
  Flow
SCV Flow Settings L/min gpm
     
0.1 b - -
1.0 3.6 1.0
2.0 7.2 1.9
3.0 10.2 2.7
4.0 14.4 3.8
5.0 19.2 5.0
6.0 24.0 6.4
7.0 31.2 8.2
8.0 39.6 10.5
9.0 65.4 17.2
10.0 114.0 30.0
     
 
HITCH FLOW (Fast Rate)
Hitch Cylinder Flow
Diameter (mm) L/min gpm
     
80/90 54.6 14.4
90/90 61.2 16.1
90/100 68.4 18.0
100/100 75.6 20.0
     
     
aat 2100 rpm
b0.1 = Minimum Flow Setting

 

AG,RX15494,3069 -19-11AUG00-1/1