HARNESS AS-ENGINE 2807518 - Caterpillar

Illustration 1 g00602507
(1) Left piston motor (travel). (2) Right piston motor (travel). (3) Swivel. (4) Valve for the left piston motor (travel). (5) Control valve (straight travel). (6) Valve for the right piston motor (travel). (7) Bank valve. (8) Piston and gear pump. (A) Drain from the piston motors (travel). (B) Oil that is returning to the hydraulic tank. (C) Supply oil that is coming from the pilot and travel speed manifold. (D) Oil supply from the hydraulic tank. (E) Oil supply to the pilot and travel speed manifold. (F) Pilot oil supply. (G) Pilot oil supply for the pilot valve (joysticks).The left piston motor (travel) (1) and the right piston motor (travel) (2) are supplied with oil from the piston and gear pump (8) through the bank valve (7) and the swivel (3) .The direction of machine movement is determined by the direction of the machine's lower structure. For normal operation, the idlers are toward the front of the machine and the piston motors (travel) are toward the rear of the machine. When the machine is arranged for normal travel and the control levers are pushed forward, the machine moves forward. The machine travels backward when the control levers are pulled backward. If the upper structure is turned 180 degrees, the operating directions for the travel levers are reversed.FORWARD Position
The travel levers are mechanically attached to the spools. When the travel levers are pushed forward, the spools in the valves for the piston motors (travel) (4) and (6) shift upward. Oil is routed from the piston and gear pump to the piston motors (travel) through the bank valve and the swivel. The piston motors move the machine forward. Refer to the Operation and Maintenance Manual, SEBU7203, "Direction and Steering Control" for more information on the operation of the travel levers.Straight Travel Valve
The straight travel valve (5) keeps the machine moving in a straight line when another hydraulic circuit