 | |
| Illustration 1 | g01023323 |
Manifold Valve (outlet) (1) Return to tank passage (2) Return oil from trailer and towing hitch hydraulic system (if equipped) (3) Load sensing signal passage (4) Load sensing signal from trailer and towing hitch hydraulic system (if equipped) (5) Pump supply passage (6) Manifold valve (outlet) (7) Pressure reducing valve (8) Pilot oil passage (9) Shutoff valve for the pilot oil (10) Supply oil from the passage of the steering priority valve (11) Supply oil to the trailer and towing hitch hydraulic system (if equipped) (12) Return oil from Electronic Pilot Valve (implement) (13) Return oil from brake circuit (14) Return to tank oil line (15) Supply oil to brake circuit | |
The manifold valve (outlet) includes the following components:
- (7) Pressure reducing valve
- (9) Shutoff valve for the pilot oil
Pressure Reducing Valve
Pump supply oil flows through a 100 micron filter that is located in the manifold valve (inlet), and through line (5) into pressure reducing valve (7). Valve (7) reduces pump supply oil from the hydraulic piston pump to 3450 ± 145 kPa (500 ± 20 psi).
This oil is used as pilot oil for the implement system and supply oil for the braking system. Part of the reduced pressure oil flows from valve (7) through internal passages and through line (15) to the master cylinder for the brake system. The rest of the reduced pressure oil flows from valve (7) through internal passages to shutoff valve (9) .
Shutoff Valve for the Pilot Oil
Shutoff valve (9) provides a means of cutting off pilot oil pressure to the main control valve. During normal operation, the pilot oil flows through the shutoff valve into passage (8). The oil then flows through passage (8) to the electronic pilot valves.
If an actuator for an implement malfunctions, or if a fault occurs in the electronic system for the implements, then the machine ECM will send a signal to the solenoid on the shutoff valve. The solenoid causes the spool in the shutoff valve to shift. When the spool shifts the flow of oil from pressure reducing valve (7) to the main control valve is blocked.
When the spool in the shutoff valve blocks the flow of oil from the pressure reducing valve to the main control valve, the spool routes the oil into internal passage (4). Passage (4) intersects with internal passage (12). The oil in passage (12) flows into the return to tank line (13) for the brake system. Line (13) routes the oil back to the hydraulic tank.