Graco A Series Instructions-Parts List Manual page 5

NOTE: The numbers in parentheses in the text refer to
reference numbers in the parts drawings and list.
Adjusting the spring tension. See Fig 3.
WARNING
Proper spring tension ensures that the fluid flow
stops when the trigger is released, to reduce the
risk of injury from fluid injection. The spring tension
is factory–set to 4050 psi (276 bar).
Proper spring tension also minimizes operator fa-
tigue by reducing trigger pull.
1. Connect the hose to the gun. Prime the pump with
the material you are spraying. Set the pump at your
normal operating pressure.
2. To set the spring tension at 4050 psi (276 bar): Trig-
ger and release the gun; the gun should shut off. If
the gun does not shut off, turn the adjustment
screw (16) in just until it does, then turn the screw one
more 1/2 turn.
3. Trigger the gun several times to be sure it shuts off
consistently.
Valve needle stem and packing replacement.
See Fig 4.
1. If fluid leaks past the v-block packing (4), the seal
housing (20{) may be loose, or the v-block packing
(4) or valve stem (28) may be worn. Tighten the seal
housing (20).
27{
{11
Fig. 4
28
{20
4
9
SERVICE
Fig. 3
2. If the gun still leaks, follow the Pressure Relief
Procedure on page 2.
3. Disconnect the hose from the gun. Disassemble the
gun and replace the v-block packing (4) and the cop-
per gasket (9).
When tightening the bushing (19), BE SURE to grip
the gun body (11), NOT the handle (12). This re-
duces the chance of loosening the connections and
damaging the gun.
12
16
CAUTION
19{
{TORQUE NOTE:
When assembling the valve seat
(27{), seal housing (20{), tube
(17{) to the gun body (11), or inlet
fitting (19) to the tube (17{), torque
the parts to 100 in–lb (11 N.m)
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