CDM816D WHEEL LOADER
55
Move the boom slide valve right to close “T” chamber and the hydraulic oil flows to “a” port from “P1”
chamber to open the one-way valve and then into the lower chamber through “A
2
” port to lift the boom.
The hydraulic oil in the upper chamber of boom cylinder returns to the oil tank through “B
2
” port, “b”
port and “T” chamber.
Fig. 3-12 Lifting Position for Boom Slide Valve
(3) Boom slide valve “Lower”
Move the boom slide valve left (as shown in the Fig.) to close “T” chamber and the hydraulic oil flows
to “b” port from “P
1
” chamber and then into the cylinder upper chamber through “B
2
” port to lower the
boom. The hydraulic oil in the lower chamber of boom cylinder flows through “A
2
” port and “a” port to
open the one-way valve and then returns to the oil tank.
Fig. 3-13 Lowering Position for Boom Slide Valve
(4) Boom “Float”
Move the boom slide valve left (as shown in the Fig..). At this time, both “A
2
” port and “B
2
” port are
connected to “b” port, “T” chamber and “P
1
” chamber, the upper and lower chambers are connected
and under low pressure. In this case, the cylinder can make the free floating state under the action of
working device weight and ground acting force.
Fig. 3-14 Floating Position for Boom Slide Valve
(5) Bucket “Tilt Up”
