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| Illustration 1 | g01440595 |
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992K Wheel Loader See auxiliary view (Z) for 854K Wheel Dozer. (1) Left steering cylinder (2) Right steering cylinder (3) Shuttle valve (steering) (4) Makeup valve (5) Relief valve (6) Steering control valve (7) Check valve (secondary steering) (8) Check valve (secondary steering pump) (9) Diverter valve (secondary steering) (10) Relief valve (secondary steering) (11) High pressure screen (secondary steering pump) (12) Oil cooler (13) Check valve (cooler bypass) (14) Connector as (orifice) (15) Relief valve (steering pilot) (16) Pressure sensor (pilot supply) (17) Pressure sensor (discharge for steering pump) (18) Gear pump (secondary steering) (19) Oil filter (steering pilot) (20) Pressure switch (steering pilot) (21) Fluid sampling valve (steering pilot) (22) High pressure screen (steering pump) (23) Filter bypass switch (steering pump case drain) (24) Oil filter (primary steering pump case drain) (25) Gear pump (steering pilot) (26) Temperature sensor (27) Hydraulic tank (steering and brake) (28) Steering pump signal pressure (29) Piston pump (steering) (30) Liquid level switch (31) Air purge screw (pump case) (32) Breaker relief valve (33) Breaker relief valve (EUROPEAN Union) (34) Expansion tank (EUROPEAN Union) (35) Pilot valve (STIC steering) (36) Selector and pressure control valve (37) Pressure switch (secondary steering) (38) Check valve (secondary pilot supply) (39) Left neutralizer valve (40) Right neutralizer valve (41) Steering quad check valve (42) Pressure reducing valve (steering) (43) Pipe plug (orifice) (44) Relief valve (steering cylinder crossover) (45) Check valve (primary pilot supply) (A) Steering pressure tap (right steer) (B) Steering pressure tap (left steer) (C) Pressure tap (steering pump) (D) Pressure tap (steering pilot supply) (E) Pressure tap (brake pump) (F) Pressure tap (rear brake accumulator) (G) Pressure tap (front brake accumulator) (H) Pressure tap (steering pump signal) | |
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| Illustration 2 | g01443576 |
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Left side view (1) Left steering cylinder (6) Steering control valve (12) Oil cooler (25) Gear pump (steering pilot) (27) Hydraulic tank (steering and brake) (29) Piston pump (steering) (33) Breaker relief valve (35) Pilot valve (STIC steering) (41) Steering quad check valve | |
The steering hydraulic system is made up of four basic circuits:
- Oil filter and oil cooler circuit
- Pilot circuit
- High pressure circuit
- Secondary steering circuit (if equipped)
The secondary steering system is optional. Some machines may also include this circuit.
The main components of the oil filter circuit and the oil cooler circuit include the following items: oil cooler (12), pilot relief valve (15), steering pilot oil filter (19), steering pilot gear pump (25) , and hydraulic tank for the steering and brake system (27).
The main components of the pilot circuit include the following items: steering pressure reducing valve (42), oil cooler (12), steering pilot relief valve (15), steering neutralizer valve (39), check valves (steering) (38), pilot valve (STIC Steering) (35), steering pilot gear pump (25), and hydraulic tank (27).
The main components of the high pressure circuit include the following items: left steering cylinder (1), right steering cylinder (2), steering control valve (6), selector and pressure control valve (36), steering piston pump (29) and hydraulic tank (27) .
Hydraulic tank (27) is on the left side of the machine next to the cab. Access is gained by opening an access door. Fill the tank to the correct oil level, if necessary. The filler cap is located on the top of the hydraulic tank for the steering and brake systems. A breaker relief valve is on the top of the hydraulic tank for the steering and brake systems.
Steering control valve (6), steering pressure reducing valve (42), and selector and pressure control valve (36) are on the left side of the machine under the operator's cab.
Pilot control valve (35) is located in the operator's cab.
Steering piston pump (29) and steering pilot gear pump (25) are located in the pump area behind the operator's cab. The steering pump has an oil filter (24) for the case drain oil. The case drain filter has a bypass check valve. This bypass check valve has a warning switch (23). When the case drain filter is bypassed, an indicator that is located in the cab will alert the operator that the case drain filter is clogged.
Steering control valve (6) and steering pilot oil filter (19) are located behind the operator's cab. Steering pilot oil filter (19) contains a bypass check valve. The bypass check valve is located in the base of the filter assembly.
Steering quad check valve (41) and steering neutralizer valves (39) and (40) are located near the articulated hitch and under the operator's cab.