Service - Graco 700N Instructions Manual

WARNING
To reduce the risk of serious injury whenever you
are instructed to relieve pressure, always follow the
Pressure Relief Procedure on page 8.
Relieve the pressure before you check or service any
system equipment.
NOTE: The fluid needle spring (7) and the air valve
spring (11) are not interchangeable. The air valve
spring (11) is slightly larger in diameter and will not fit
into the fluid valve cavity. See Fig. 3.
Air Valve Service
1. If there is air leakage at the air valve needle (12),
remove the trigger and unscrew the air valve as-
sembly. See Fig. 3.
2. Clean and inspect the needle (12), spring (11) and
air valve (13) for wear or damage. Replace if
needed.
3. Apply a few drops of light-weight machine oil to the
air valve needle (12) and reassemble the air valve.
12 307–452

Service

Fluid Packing Replacement
1. If leakage occurs at the fluid needle packing nut
(9), tighten the nut. If leakage does not stop, re-
move the fluid adjusting valve knob (6), spring (7)
and needle (1). See Fig. 3.
2. Unscrew the packing nut (9) and remove the old
packings (10). A small hooked tool can be used to
remove packings from the cavity. Clean and in-
spect all the parts for wear or damage, replacing
parts as needed.
3. Lubricate the new packings and the needle with
lightweight oil and insert the packings into the cav-
ity in the order shown in Fig. 3, Detail D.
4. Install the needle (1). Slide the packing nut (9) onto
the needle before inserting the needle into the
packing cavity. Then install the spring (7) and the
fluid adjusting knob (6) into the gun body.
5. Turn the fluid adjusting knob (6) in until it bottoms
out, then back it out six full turns for proper spring
adjustment.
6. With the trigger released, screw the packing nut (9)
in until the packings are fully compressed, then
back it off until the needle moves freely when the
gun is triggered.
NOTE: For the best fluid packing life, lubricate the gun
daily as explained in Maintenance.