CP56, CS56, CP64, CS64, CP74 and CS74 Vibratory Compactors Propel System Caterpillar

Illustration 1	g01415881
Left Side of Machine (1) Front charge filter (2) Rear charge filter

The hydraulic filters are located under the operator platform on the left side of the machine.

Charge oil from the steering hydraulic system flows through front charge filter (1). This oil is directed to the vibrator pump and to the drum pump. Charge oil from the fan hydraulic system flows through rear charge filter (2) to the axle pump and to the shift solenoid.

The housing of each charge filter contains a bypass valve. If the pressure differential across the filter is greater than 350 kPa (51 psi), the bypass valve opens. When the bypass valve is open, charge oil flows to the hydraulic tank. As a result, the charge oil bypasses the hydrostatic loop.

Illustration 2	g01415882
Left Side of Machine (3) Pressure switch

Pressure switch (3) is installed in the outlet line of the front charge filter. Contact "A" of the pressure switch is connected to the common return line at terminal "J1-35" of the engine ECM. Contact "B" of the switch is connected to terminal "J1-45" of the engine ECM.

On start-up, the switch closes when the pressure reaches 1400 kPa (203 psi). During operation of the machine the switch will open and the indicator will illuminate when the pressure is less than 1100 kPa (160 psi). The indicator will remain illuminated until the pressure reaches 1400 kPa (203 psi).