Yanmar YM276 Service Manual page 416

70-1 5-4
Hydraulic Lift and Implement Hitches
MAIN RELIEF VALVE
Coat all mating parts and gaskets with Transmission
-
Hydraulic
Oil prior to assembly and installation.
REMOVAL
1. Remove plug (A).
2. Remove shim (C) and spring (DI.
3. Remove screw (E) with Special Tool TOL-9302000. (see
p. 70-00.4)
4. Carefully extract valve seat (GI, and valve body (F), with
hook on Soecial Tool.
A
-
Plug
B
-
Packing
C
-Shim
F -Val- Body
G
-
Valve % s t
H
-
LoskSsnw
D
-
Spring
I -O-ring
E
-
Scrnv
B o o
\
r
INSPECTION
1. Examine valve seat (G) and valve body (F) for damage, burr
@
0 6 0
and contaminants.
,--.
2250620
2. Free length of spring ( D ) should be 50.7 mrn (1.996 in.) and
should mmpress to 42 mm at 324 N (1.654 in. at 73.0 lbs).
There are five shim (C) thicknesses available:
0.1 mm (0.0039 in.)
0.2 mm (0.0079 in.)
0.3 mm (0.01 18 in.)
0.5 mm (0.0198 in.)
1.0 mm (0.0393 in.)
Replace spring or shim as necessary.
3. Replace O-ring ( I ) as necessary.
INSTALLATION
1. Carefully install valve body (F) with its valve seat (G
).
2. Tighten screw (El.
3. Install spring (D) and shim (C)
4. Before installing plug (A), check that packing (B) is free from
damage and positioned correctly.
5. Tighten plug (A).
/.