HANDLE GP-MOD 2953430 - Caterpillar

Main Hydraulic Pumps
The main hydraulic pump is referred to as an ESP (Electronic Standardized Pump) pump. The main hydraulic pumps consist of two variable displacement piston pumps that are contained in an integral housing. The two main pumps are referred to as the drive pump and the idler pump. The engine directly powers the drive pump through a mechanical connection to the engine flywheel. An internal gear set inside the pump housing transfers the rotational power from the drive pump to the idler pump. The drive pump and the idler pump are identical in construction and operation. The pumps are sometimes referred to as side by side pumps.The drive pump and the idler pump regulators are controlled by the electronic control system. A proportional reducing valve on each regulator controls the output flow of the pumps by changing the hydraulic signal pressure that flows to the actuator piston in the pump regulators.Note: Refer to the appropriate sections in this manual for more information.