Reassembly; Check Valve Adjustment - Graco A Series Instructions - Parts Manual

Reassembly

1. See the Parts drawing on page 6. Install the throat
gland/packing stack (12*) into the outlet housing (1),
with the lips of the v-packings facing down. The
stack is preassembled. Do not disassemble the
stack.
2. Install the bearing (14*) in the packing nut/wet-cup
(15) and install the packing nut in the outlet housing
(1). Tighten the packing nut/wet-cup just enough to
prevent leaking, but no tighter. Overtightening com-
presses the packings and causes leaking.
3. Install the ball stop pin (9) in the desired holes in the
displacement rod (8).
4. Lubricate and install the o-ring (16*) on the piston
body (13).
5. Lubricate and install the gland/packing stack (11*)
on the piston (13) with the lips of the v-packings fac-
ing up. The stack is preassembled to the required
dimension and includes up to three shims (S). Do
not disassemble the stack.
6. Place the ball (4) on the piston (13) and screw the
piston into the displacement rod (8). Torque to
150-175 ft-lb (203-237 N•m).
7. Lubricate the outer surface of the displacement rod
(8) and slide it up into the outlet housing (1).
312745A
8. Install an o-ring (3*) on the groove at the bottom of
the outlet housing (1). Carefully slide the cylinder (2)
straight up into the outlet housing, being careful not
to scratch or mar the polished inner surface of the
cylinder.
9. Place an o-ring (3*) in the groove of the intake valve
housing (6). Install the intake ball (4). Insert the ball
stop pin (5) in the desired holes.
10. Install the four tie bolts (7) through the outlet hous-
ing (1) and into the intake valve housing (6). Tighten
evenly and torque to 57-63 ft-lb (77-85 N•m).
11. Reconnect the displacement pump to the air motor
as described in Hydra-Clean package manual
312585.

Check Valve Adjustment

The piston and intake check valves are factory-set for
light viscosity fluids. This setting minimizes surging at
pump stroke changeover. To adjust the valves for
heavier viscosity fluids:
1. Relieve the pressure, page 4.
2. Unscrew the four tie bolts (7) and remove the intake
valve (6) and cylinder (2).
3. Remove the ball stop pins (9 and 5) and move them
to a higher set of holes to increase the ball travel.
4. Reassemble.
Repair
5