Pump Service Model 804594 (Dd6814) - Graco AquaMax 804594 A Series Instructions-Parts List Manual

Pump Service — Model 804594
Always relieve the pressure before you begin.
For Pressure Relief,
see page 5.
NOTES:
D The following metric wrenches are needed: 5 mm,
13 mm, and 22 mm.
D There is a tool kit to aid in servicing the pump:
Tool Kit 800271 includes tools to aid in removing
packing retainers.
D Repair kits are available. See the individual repair
sections in this manual, and see the instructions
that come with the kits for location of parts. For the
best results, use all parts in the kits.
Valves
NOTE: For a set of six valves, order 801472. See
Pump Repair Kits on page 20.
1. Remove the hex plug from the manifold using a 22
mm socket.
2. Examine the O-ring under the hex plug, and
replace if cut or distorted.
3. Remove the valve assembly from the cavity; the
assembly can come apart.
4. Install the new valve. Install the O-ring and hex
plug, and torque to 45 N-m (33 ft-lb).
NOTE: Retorque the plug after 5 hours of
operation.
Pumping Section
1. Remove the eight capscrews and lockwashers
from the manifold using a 5 mm wrench.
2. Carefully separate the manifold from the
crankcase.
NOTE: You might have to tap the manifold lightly
with a soft mallet to loosen it.
CAUTION
Keep the manifold properly aligned with the ce-
ramic plungers when removing to avoid damage to
the plunger or seals.
3. Carefully examine each plunger for any scoring or
cracking, and replace as necessary.
12
309016
AquaMax DD6814
Servicing the Plungers
NOTE: Plunger Repair Kits are available for replacing
retainers, O-rings, washers, and backup rings for three
cylinders. See Pump Repair Kits on page 20.
1. Loosen the plunger retaining nut five to six turns,
using a 13 mm wrench. Push the plunger toward
the crankcase to separate the plunger and
retaining screw.
2. Remove the nut from the plunger, and examine the
O-ring, backup ring, and copper bearing/gasket
washer. Replace these parts, if necessary, using
parts from Plunger Repair Kit 801474.
3. Remove the plunger and flinger from the plunger
shaft. Clean, examine, and replace parts as
necessary.
4. Inspect the plunger shaft for oil leakage from the
crankcase. If leaking is obvious, replace the oil
seals. If leaking is very minor, do not remove the
seals, because they cannot be reused. Oil Seal
Kits are available to replace the seals. See Pump
Repair Kits on page 20.
5. Lightly grease the flinger and oil seal if they are
being replaced, and put them on the plunger shaft.
Then install the plunger.