Brandt SB4000, Operator'S Manual

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62
Closed Center (Pressure Compensated) - HM4C model only
On a pressure compensated system the amount of oil that is allowed to flow through the hydraulic motor is
regulated by a metering orifice in the pressure port adapter. Three different sizes of orifices are supplied with the
HM4C model pump to allow flexibility in the flow required for individual sprayer needs. The smaller the orifice the
less hydraulic oil goes through the motor, so the pump will run slower and the flow of liquid pumped and the spray
pressure will also be less. As the hydraulic oil flow is increased (by installing a larger orifice), the amount of liquid
being pumped and the spray pressure is also increased.
Installing and Removing the Metering Orifice
1. Shut off the hydraulic system.
2. Disconnect the line to the pressure port of the hydraulic motor.
3. Remove the adapter from the motor using a 1-1/16'’ wrench.
4. Make sure the O-ring is on the metering orifice before installing it in the port adapter.
5. The orifice is removed or installed in the port adapter by tapping it either in or out of the adapter.
a. To remove - tap the orifice out from the small end of the adapter.
b. To install - tap the orifice in from the large end of the adapter. The orifice is seated when a
snap sound is
heard.
Adjusting Centrifugal Pump Output
1. Install the #1 size orifice (smallest) in the motor.
2. Prime the centrifugal pump by opening the upper stop cock in the pump until a steady strem of water flows out.
3. Open the Bypass Adjusting Screw in the Hydraulic Motor three (3) turns.
4. Start the tractor and allow the hydraulic oil to circulate for approximately 10 to 15 minutes or until adequately
warmed.
5. Close and lock down the bypass adjusting screw in the hydraulic motor.
6. Set the tractor hydraulic flow control to the maximum flow setting (Rabbit).
7. Close the Agitation Valve and the Throttle Valve; open the Spray Pipe Ball Valves.
8. With the pump running, open the Throttle Valve until the pressure gauge indicates the desired spraying pressure.
9. Open the agitation line valve until sufficient agitation is observed. Then, if spray pressure drops, readjust the
Throttle Valve to restore to the desire pressure.
10. If a sufficient boom pressure cannot be attained, install the #2 size orifice and repeat Steps 7 through 9 .