Hydraulic System Operation - Yanmar YM276 Service Manual

HYDRAULIC SYSTEM OPERATION
270-05-1
GENERAL
A
-
Re~swoir
ISumpl
C
-
Paper Canridge Filtar
E
-Control Vahe G
-
Lifting Cylinder
B
-
Filter Screen
D
-
Hydraulic Pump F
-
Relisf
Valve H
-
Safety
Valve
m - p r e s s u r i z e d Oil
0
.Pr-re Free Oil
The hydraulic system of the tractor includes an oil reser-
voir (Transmission case) (A), filter screen (6). hydraulic
oil filter (cartridge type)
(C), hydraulic pump (Dl,
hydraulic control valve (E), relief valve (F), hydraulic l i f t
cylinder
(G)
and safety valve (HI.
The transmission case serves as the hydraulic reservoir.
A mesh screen in t h e filter housing, located on the bottom
of the transmission case. filters the hydraulic oil.
, - - .
A replaceable paper cartridge type filter, located on the
hydraulic inlet line, further filters the hydraulic oil filtered
bv the mesh screen.
The hydraulic pump
(D)
draws oil through the two filters
from the reservoir. The pump then feeds oil through the
hydraulic cylinder head t o the hydraulic control valve
(E).
A pressure relief valve (Fl located in the hydrauliccylinder
head protects the system from excessive o i l pressure.
With the hydraulic control valve in neutral position, all
oil flows through the valve to the reservoir. When the
control valve is moved rearward t o raise the hydraulic lift,
oil is diverted t o the hydraulic cylinder. Upon completion
of the hydraulic lift operation, the valve is again neutralized
andall oil is routed to the reservoir.