CORE ASSEM. 4N5908 - Caterpillar

Port "M5"
Each rotating group in the pump is equipped with a port that is labelled "M5". These ports are located on the opposite side of the pump housing. Each of these ports is plugged. The pressure on one side of the servo piston can be measured at port "M5". On the left material feed pump, port "M5" on the shaft end of the pump housing can be used to measure forward servo pressure for the left conveyor. Port "M5" on the end of the pump housing can be used to measure reverse servo pressure for the left auger. On the right material feed pump, port "M5" on the shaft end of the pump housing can be used to measure reverse servo pressure for the right auger. Port "M5" on the end of the pump housing can be used to measure forward servo pressure for the right conveyor.Port "M14"
Each rotating group in the pump is equipped with a port that is labelled "M14". These ports are located on the direction control valves. Each of these ports is plugged. Case drain pressure can be measured at port "M14".Electronic Directional Control Valve
Each rotating group contains a direction control valve and a servo piston. Each direction control valve is equipped with two EDCs. The EDCs are proportional solenoids. The function of each EDC is shown in the following list:EDC for port "A"
On the left material feed pump, this EDC controls forward operation of the left auger. On the right material feed pump, this EDC controls reverse operation of the right auger.EDC for port "B"
On the left material feed pump, this EDC controls reverse operation of the left auger. On the right material feed pump, this EDC controls forward operation of the right auger.EDC for port "C"
On the left material feed pump, this EDC controls reverse operation of the left conveyor. On the right material feed pump, this EDC controls forward operation of the right conveyor.EDC for port "D"
On the left material feed pump, this EDC controls forward operation of the left conveyor. On the right material feed pump, this EDC controls reverse operation of the right conveyor.Charge Relief Valves
The pump housing is equipped with a charge relief valve. The charge relief valve in each material feed pump is set to 2800 172 kPa (405 25 psi). This valve is mechanically adjustable. However, since charge oil is supplied from the propel system, and both propel pumps contain charge relief valves, adjustment of the charge relief valve on the material feed pump may have no effect on charge relief pressure. The charge relief pressure will be controlled by the relief valve with the lowest setting. The valve on the propel pump is set lower than the valve on the material feed pump.The function of each makeup and relief valve is shown in the following list:Makeup and Relief Valves
Each rotating group of the material feed pump is equipped with two makeup and relief valves. The relief section of the valves in