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 Remote Hydraulic Connections section, Implement Connection Example 1— Pressure Control Valve Applications (Grain Drills Or Air Seeders With Constant Down-Pressure System) in this Operator's Manual.
   • Auxiliary flow control valves (vacuum flow control)—Completely open implement flow control valve and adjust tractor flow rate to desired setting. See Remote Hydraulic Connections section, Implement Connection Example 4— Planter with Vacuum Motor and Return Line to SCV Using Motor Return Tip in this Operator's Manual.
   • Cylinder functions, where line or orifice restrictions control flow—Adjust tractor flow control to point where function speed begins to decrease. See Remote Hydraulic Connections section, Implement Connection Example 2—Motor Application Using Motor Case Drain in this Operator's Manual.
   • 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 implement is so equipped.
   
   

NOTE: Flow measurements are made without steering or hitch being used.

MAIN HYDRAULIC PUMP FLOW (APPROXIMATE)
Engine rpm	Pump	Pump Flow
1000	63 cc	80 L/min (21 gpm)
2000	63 cc	160 L/min (42 gpm)
1000	85 cc	108 L/min (28.5 gpm)
1500	85 cc	162 L/min (43 gpm)
2000	85 cc	216 L/min (57 gpm)

SCV FLOW OUTPUT (APPROX.1)
SCV Flow Settings	Flow
0.1 2	—
1.0	3.4 L/min (0.9 gpm)
2.0	7.5 L/min (2.0 gpm)
3.0	12.5 L/min (3.3 gpm)
4.0	17.4 L/min (4.6 gpm)
5.0	20.8 L/min (5.5 gpm)
6.0	27.6 L/min (7.3 gpm)
7.0	40 L/min (10.6 gpm)
8.0	75 L/min (19.8 gpm)
9.0	110 L/min (29.3 gpm)
10.0	131.7 L/min (34.8 gpm)

Hitch Flow
Hitch Cylinder	Flow
Diameter (mm)	L/min	gpm
90/90	59.5	15.7
90/100	66.4	17.5
100/100	73.4	19.4
100/112	82.6	21.9
112/112	92.1	24.3