Hitachi NT65MA3 - 2-1/2 Angled Finish Nailer Service Manual page 21

Air leakage point
(C) Blade guide
(D) Air outlet, valve bushing
(E) Control valve (1)
(F) Control valve (2)
(G) Cap (A)
With control valve OFF
The Cylinder O-Ring (I.D 63.1) [12] is
abnormal (broken or damaged).
The seal surface of the Body Ass'y
[30] is abnormal ( c portion).
The Valve Packing [16] is damaged.
The O-Ring (1AP-3) [19] of the
Plunger [18] is abnormal (worn,
broken or damaged).
The O-Ring (S3) [20] of the Plunger
[18] is abnormal (worn, broken or
damaged).
The screw of the Valve Bushing [22]
is loose.
The O-Ring (I.D 11) [66] on Valve
Piston (B) [65] is abnormal (worn,
broken or damaged).
The lower O-ring (I.D 8.8) [63] on
Valve Piston (B) [65] is abnormal
(worn, broken or damaged).
The O-Ring (S-18) [62] on Valve
Bushing (B) [61] is abnormal (broken
or damaged).
The inside surface of the valve
chamber of the Body Ass'y [30] is
abnormal.
The O-ring (I.D 1.8) [69] on Plunger
(A) [68] is abnormal (worn, broken or
damaged).
Valve Bushing (A) [70] is abnormal
(sliding surface of Plunger (A) [68] is
deformed or scratched).
Gasket (B) [48] is damaged.
The Hex. Socket Hd. Bolt M5 x 16 [50] is loose.
The seal surface of the Body Ass'y [30] or Cap (A) [49] is abnormal (broken,
deformed or scratched).
--- 18 ---
Possible cause
With control valve ON
The Piston Bumper [25] is abnormal
( d or e portion is damaged,
deformed or cracked).
The Piston [15] is abnormal (driver
blade or sealed face is deformed).
The e surface of the Body Ass'y [30]
is deformed.
The upper O-Ring (I.D 8.8) [63] on
Valve Piston (B) [65] is abnormal
(worn, broken or damaged).
The Head Valve O-Ring (I.D 16.8)
[60] on Valve Bushing (B) [61] is
abnormal (broken or damaged).
* The Top surface of the valve chamber
of the Body Ass'y [30] is abnormal
( f portion).
The inside of the O-ring (S-4) [64] on
Valve Piston (B) [65] is abnormal
(worn, broken or damaged).
Plunger (A) [68] is abnormal (sliding
surface is deformed or scratched).