SPRING 3Y9740 - Caterpillar

oils acquire wear metals and contaminants from hydraulic cylinders, motor seals, and hydraulic hoses. Dirt can also enter the hydraulic system through vent filters in vented systems and through seals of the hydraulic cylinders. Cleanliness of hydraulic oils is critical for the operation of hydraulic system, in particular the operation of hydraulic valves that are typically of very tight tolerances. Cleanliness of the hydraulic oils is especially important to modern hydraulic systems. These systems are built with close tolerances and precise designs that require low level of contamination and appropriate filter performance. Follow the recommendations in the Operation and Maintenance Manual of your machine.Cat hydraulic filters are available in Standard, Advanced, and Ultra High efficiency. Fire resistant hydraulic filters of Ultra High Efficiency are also available.Particle count of hydraulic oils to determine cleanliness is recommended. Filtering of the oil that is filled into the hydraulic system is recommended to achieve a cleanliness level of the oil of "ISO 16/13". Refer to this Special Publication, "Contamination Control" for details on the contamination requirements and ISO code information.