Hitachi NT65MA3 - 2-1/2 Angled Finish Nailer Service Manual page 27

(b) Reassembly
Disassembly procedures should be followed in the reverse order. Note the following points:
Be extremely careful to prevent the entry of foreign particles into the control valve section.
Thoroughly apply grease to the O-ring (I.D 1.8) [69] on Plunger (A) [68], O-ring (S-4) [64], O-ring (I.D 8.8) [63]
and O-ring (I.D 11) [66] on Valve Piston (B) [65], and the shaft of Plunger (A) [68] as shown in Fig. 19.
As shown in Fig. 19, install Valve Bushing (A) [70] so that the roll pin groove in Valve Bushing (A) [70] will be
aligned with the roll pin hole in the Body Ass'y [30]. First, insert a roll pin puller (3 mm (.118") dia.) into the roll
pin hole. Then, upon confirming that the puller passes through the hole, drive in the Roll Pin D3 x 28 [54].
If an attempt is made to drive the roll pin with force when the roll pin groove in Valve Bushing (A) [70] is
not aligned with the roll pin hole in the Body Ass'y [30], it will damage the periphery of Valve Bushing (A)
[70] and prevent disassembly or reassembly.
Body Ass'y [30]
Roll pin hole
Roll pin groove
After assembling, check that Plunger (A) [68] moves smoothly.
Apply grease to the stem.
Roll Pin D3 x 28 [54]
Assemble
Plunger (A) [68]
Valve Bushing (A) [70]
Fig. 19
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Coat the O-ring
groove's shaft with
grease.
Valve Bushing (A) [70]