Hitachi NT 65A3 Technical Data And Service Manual page 25

Problem
3) Head of a nail Air pressure is too low.
driven into a Workpiece is very hard.
workpiece
protrudes
from the wood
surface.
Driver blade is worn.
Piston O-ring is abnormal
(worn or damaged).
Cylinder's internal surface is
abnormal (worn or rough).
Unspecified nails used.
4) Nails clog the
mechanism.
< Improper nail feed >
See <Magazine> in item 1).
Driver blade worn.
< The driver blade has not
returned completely. >
See <Output section:
Piston, driver blade, etc.>
in item 1).
Plunger O-ring (inside the
5) Single
valve bushing) is abnormal
actuation
(worn or broken).
impossible.
O-ring (P-9, inside the valve
sleeve) is abnormal (worn
or broken).
O-ring (I.D 10.7) at the
6) Piston
outside of the valve bushing
actuates just
is abnormal (worn,
by pulling the
damaged or broken).
trigger (when
single
actuation is
selected).
Possible cause
Inspection method
Drive a nail into soft wood
workpiece and check if the
head protrudes from the
wood surface.
Operate the nailer without
nails and check if the driver
blade is projected from the
nose tip.
Disassemble the output
section and check the
piston O-ring, O-ring and
the inner/outer surfaces of
the cylinder for abnormal
condition.
Check if the nails are
specified ones.
Check if they move
smoothly after putting nails,
and check if the nail feeder
operates smoothly.
Check if the driver blade tip
is worn.
Perform idle driving or
actually drive with nails, and
check if the driver blade has
returned completely.
Set the single actuation/
contact actuation selector to
the single actuation.
Perform idle driving once
and keep the trigger pulled
backward. Check that no
air leaks from the inside of
plunger (B) and valve
sleeve (A).
Disassemble the control
valve and check the O-ring.
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Remedy
Adjust for 5 to 8.5 kgf/cm
Do not use unspecified
workpieces.
Replace the driver blade.
Replace the defective part.
Use specified nails.
See <Magazine> in item 1).
Replace the part.
See <Output section: Piston,
driver blade, etc.> in item 1).
Replace the defective part.
Replace the defective part.
2
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