New Holland T8010 Manual page 850

Retract
When the remote hydraulic control lever is moved to
the retract position, the main valve spool is shifted to
the right a fixed distance by the proportional solenoid
pressure supply. The position of the main valve spool
determines the flow rate to the retract port.
As the main valve spool is shifted, flow from the
intermediate pressure area is directed to the lower
port and to the left hand side of the load check
plunger. T he plun ger is for ced to m ove r i ght
unseating the load check pilot poppet. This reliefs the
pressure on the spring side of the main poppet back
to tank. The plunger contacts and unseats the main
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1. EXTEND PORT
2. RETRACT PORT
3. LOAD CHECK PLUNGER
4. MAIN VALVE SPOOL
5. PRESSURE COMPENSATED FLOW CONTROL SPOOL
6. PROPORTIONAL SOLENOID (EXTEND)
7. PROPORTIONAL SOLENOID (RETRACT)
8. PFC PUMP SUPPLY
Section 35 - Hydraulic Systems, 3PT - Chapter 5
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35-5-19
poppet which allows the return oil to flow back to the
inlet side of the filter base. (Differential pressure
between the raise port and the spring side of the
main poppet also contribute to unseating the main
poppet).
At the same time work pressure is communicated to
the signal checks through the center drilled passage
in the main valve spool. The signal check is forced off
the seat and the signal pressure is then directed to
the pump compensator to increase PFC pump flow.
The work pressure is also directed to the relief signal
ch eck to l imi t the re mote sec tion s max imu m
pressure.
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9. REGULATED PRESSURE SUPPLY
10. BACK TO TANK
11. SIGNAL LINE TO COMPENSATOR
12. TO REMOTE SIGNAL RELIEF VALVE
13. PILOT DRAIN
14. SIGNAL CHECK TO PUMP COMPENSATOR
15. SIGNAL CHECK PILOT RELIEF
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