ADAPTER GP-BASE END CHANNELS 1288556 - Caterpillar

Illustration 1 g01077735
(1) Left tow point cylinder (2) Right tow point cylinder (3) Right tow point solenoid valve (4) Return line to hydraulic tank (5) Pressure line from auxiliary pump (6) Left tow point solenoid valve
Illustration 2 g01081532
(2) Right tow point cylinder (7) Tow point (8) Tow armThe grade control system is controlled by tow point solenoid valves (3) and (6). There is one tow point solenoid valve on each side of the machine. Each valve controls a tow point cylinder (1) and (2). The cylinder moves the tow point (7) upward or the cylinder moves the tow point downward. The grade control systems on both sides of the machine work identically to each other. The grade control systems on both sides of the machine work independently of each other. The valves can be controlled manually or the valves can be controlled with the automatic grade and slope controls. The cylinders are connected to the machine frame and tow arms (8). When the cylinders are moved, the tow arms change the angle of attack of the screed. This causes the thickness of the mat to change.Note: For information on the automatic grade and slope controls, refer to Operation and Maintenance Manual, KEBU7022, "Setting Up The Screed".
Illustration 3 g01081470
Typical right hand screed control boxThe three-position manual control switches are spring centered. The switches are located on the screed in the screed control boxes.When the engine is running and one of the control switches is moved upward, the corresponding solenoid valve will shift to the right. The oil from pressure line (5) is routed through the valve to the piston rod end of the tow point cylinder. The cylinder retracts in order to raise the tow point. The return oil is routed through the valve to return line (4). The return line routes the oil to one of the return manifolds.When the engine is running and one of the control switches is moved downward, the corresponding solenoid valve will shift to the left. The oil from pressure line (5) is routed through the valve to the head end of the tow point cylinder. The cylinder extends in order to lower the tow point. The return oil is routed through the valve to return line (4). The return line routes the oil to one of the return manifolds.