Hitachi ZW 310-6 Operator's Manual page 327

[ Line Filter in Steering Circuit (Reducing Valve Unit) ]
8. Remove plug (4) with O-ring (5).
9. Take out filter element (3) inside, and clean it by
applying air or cleaning solution from the oil flow
outlet side.
10. Install the cleaned filter, O-ring and tighten plug (4).
MAINTENANCE
7-49
3
5
4
3
Oil Flow
5
4
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