BUSHING 3603135 - Caterpillar

Introduction
Steering System Schematic
(1) Hydraulic oil filter. (2) Steering relief valve. (3) Steering pump. (4) Parking brake and speed shift valve. (5) Steering control unit (SCU). (6) Priority valve. (7) Strainer. (8) Hydraulic oil tank. (9) Steering cylinders.The main components of the steering system are: steering pump (3), steering control unit (SCU) (5), hydraulic oil tank (8), and steering cylinders (9).
Under Platform
(3) Steering pump.Steering pump (3) pulls oil from hydraulic tank (8) through strainer (7). The steering pump is driven off of the rear of the propel and vibratory pumps. The propel and vibratory pumps are driven by the pump drive group on the rear of the engine.
Steering Control Unit Location
(5) Steering control unit (SCU). (10) Console.Oil flows from steering pump (3) to steering control unit (SCU) (5). The steering control unit is located at the bottom of the steering column just under console (10). The steering control unit is closed center and load sensing.
Location At Rear Of Seat
(8) Hydraulic oil tank.Hydraulic oil tank (8) provides hydraulic oil for the steering, propulsion and vibration systems. The hydraulic oil tank is located to the rear of the operator platform.
Under Platform
(9) Steering cylinder.When the steering wheel is turned, two double acting steering cylinders (9) receive oil from steering control unit (5) so that the compactor can make the desired turn. When the steering wheel is not turned, oil from the steering pump maintains pressure at the steering control unit. There is a small amount of oil required to make up for losses through the bleed orifice in the steering pump. With the steering control unit in the spring centered position, no oil goes to the steer cylinders.
Location At Rear Of Seat
(1) Hydraulic Oil Filter.If hydraulic oil filter (1) becomes plugged, a pressure drop is created across the hydraulic oil filter. When the pressure decreases 350 kPa (50 psi) across the filter, the filter bypass valve opens. Oil then flows through the filter bypass valve to the check valve which is part of parking brake and speed shift valve (4). When the pressure decreases 1220 kPa (175 psi) across the passage between the bypass and check valve, the check valve opens and the oil flows to the hydraulic tank. The check valve prevents the brake pressure from ever dropping below 1550 kPa (225 psi). A pressure drop of 172 kPa (25 psi) shows red on the visual bypass indicator which indicates the hydraulic oil filter should be changed.Steering Pump
Steering Pump
(1) Priority valve spool. (2) Pilot load sensing signal port. (3) Bleed orifice. (4) Charge outlet port. (5) Unloading relief valve. (6) Steering pump gears.The steering pump is a fixed displacement gear pump driven off the rear of the vibratory and propulsion pumps. The steering pump supplies oil to the steering, propel and vibratory systems. Within the pump is priority valve spool (1) which is a pressure compensated flow divider. The priority valve spool divides flow between the steering circuit and the charge circuit. The steering circuit has priority. Return flow from the