Komatsu PC88MR-10 Shop Manual page 121

Breather
(PC88MR-PM38-041-K-00-A)
1. Nut
2. Cover
3. Filter element
4. Case
5. Valve assembly
6. Body
Prevention of negative pressure in tank
Since the hydraulic tank is pressurized and sealed, if the oil level in it decreases, negative pressure is
generated in it. At this time, valve assembly (5) is opened by the differential pressure from the ambient
pressure, and ambient pressure is transmitted into the tank to prevent generation of negative pressure in
the tank
(Set pressure of air intake valve: 2 ± 0.3 kPa {0.02 ± 0.003 kg/cm
PC88MR-10
10 Structure and function
2 })
Hydraulic tank
10-43