SEAL-O-RING 1433629 - Caterpillar

Illustration 1 g06174211
Under Operator Platform
(1) Steering manifoldSteering manifold (1) is located under the operator platform, above and in front of the pump stack. A panel on the right side of the machine provides access to this component.Note: The steering manifold shown in the illustration is the standard component. Machines with a drum offset system are equipped with a different hydraulic manifold. Refer to "Drum Offset System" in this document for more information.Steering manifold (1) contains components used to control the steering system.On machines that are not equipped with the optional drum offset system, steering manifold (1) is similar. In this case, the manifold is slightly smaller and does not contain the solenoid valves and counterbalance valves for the drum offset systemSteering manifold (1) shown also contains control valves for the drum offset.Note: Refer to "Drum Offset System" for additional information about the components and controls of the drum offset system.
Illustration 2 g06174640
Steering Control Manifold
(2) Compensator spool
(3) Front counterclockwise solenoid
(4) Front clockwise solenoid
(5) Counterbalance valves
(6) Main relief valve
(7) Shunt valve
(8) Warmup valve
(9) Margin spoolThe steering control valve is controlled by the machine ECM. This valve is controlled by two solenoids. Front clockwise solenoid (4) causes the machine to turn right. Front counterclockwise solenoid (3) causes the machine to turn left. The steering control valves direct oil to one end of the steering cylinder while opening the other end to the hydraulic tank.Note: The standard steering control manifold is shown in the illustration. If the machine is equipped with the optional drum offset system, a single control manifold is used to control the steering system and the drum offset system. Refer to "Drum Offset System" for additional information about the components and controls of the steering system.Steering shunt valve (7) enables and disables the steering system. The machine ECM energizes the steering shunt solenoid to enable the steering system. In this condition, the shunt valve is closed and oil from the steering pump is routed to the steering control valve. When the shunt solenoid is de-energized, the shunt valve opens and sends oil from the pump directly to the hydraulic tank. In this condition, the steering system is disabled. The machine ECM disables the steering system when the machine electronic control system registers a level-three fault.Main relief valve (6) limits steering system pressure to 20000 1000 kPa (2900 145 psi). When the main relief valve is open, steering oil flows into the hydraulic tank.Margin spool (9) regulates the flow of supply oil to the steering system. When the flow of supply oil into the system is greater than the demand of the system, the margin spool directs unused oil into the hydraulic tank.The shuttle valves (not shown) compare pressure requirements and send the highest pressure requirement to the margin spool. One shuttle valve compares the pressure at the rod end of the cylinder and the pressure at the head end of the cylinder. A second shuttle valve compares the highest pressure in the steering cylinder and the external load-sensing pressure