Hitachi NT 65M2 Technical Data And Service Manual page 24

Groove of the
Exhaust Cover [5]
Exhaust Cover [5]
Fig. 12
(2) Disassembly and reassembly of the Valve Bushing [26], Plunger [22], etc. (See Fig. 13.)
[Tools required]
Socket wrench (14 mm)
Flat-blade screwdriver
(a) Disassembly
Remove the Valve Bushing [26] with a socket wrench (14 mm). The Valve Packing [20] and the Spring [21]
can now be removed.
Remove the Knob [28] and the Retaining Ring (E-type) for D4 Shaft [27] then the Plunger [22] can be
removed from the Valve Bushing [26].
(b) Reassembly
Disassembly procedures should be followed in the reverse order. Note the following points:
Apply grease to the O-ring (1AP-3) [24], O-ring (S3) [23] and the O-ring (S-10) [25].
Mount the Retaining Ring (E-type) for D4 Shaft [27] to the Plunger [22] then press the Knob [28] against
the Retaining Ring (E-type) for D4 Shaft [27] to mount it.
Exhaust Cover [5]
Fig. 13 Disassembly and reassembly of the valve bushing, plunger, etc.
O-ring (I.D 20.8) [9]
Head Valve (A) [10]
O-ring (S-10) [25]
O-ring (S3) [23]
O-ring (1AP-3) [24]
(b) Reassembly
Disassembly procedures should be followed in the reverse
order. Note the following points:
Apply grease to the inside of the Cylinder [13], O-ring
(I.D 31.7) [11] and the Cylinder O-ring (I.D 59.6) [15]
before reassembly.
Apply grease to the sliding surface a of the Exhaust
Cover [5] and Head Valve (A) [10] and charge about
0.5 g (.018 oz) of grease in the groove of the Exhaust
Cover [5] (Fig. 12).
Apply grease to the lip portions b and c of Head Valve
(A) [10] (Fig. 12).
Apply grease to the O-ring (I.D 20.8) [9].
Mount the O-ring (I.D 20.8) [9] to Head Valve (A) [10],
then mount it to the Exhaust Cover [5].
Knob [28]
Valve Bushing [26]
Plunger [22]
Spring [21]
Valve Packing [20]
--- 21 ---
Retaining Ring (E-type)
for D4 Shaft [27]