Graco 2900 psi - Manual (Page 8)

8 308524
Pump Service
Repair kits are available. See Pump Repair Kits on page 13. For the best results, use all parts in the kits.
Relieve the pressure
(see page 5) before you
proceed with service.
NOTES:
D The following metric wrenches are needed:
10 mm, 13 mm, and 30 mm.
D There are two tool kits to aid in servicing the pump.
Kit 800298 is used to ease installation of packings.
Kit 800271 includes the items in 800298 and tools
to aid in the removal of packing retainers.
Valves
NOTE: For a set of six valves, order 801472.
1. Remove the hex plug from the manifold using a
30 mm wrench.
2. Examine the o-ring under the hex plug and replace
it if it is cut or distorted.
3. Remove the valve assembly from the cavity; the
assembly may come apart.
4. Install the new valve. Install the o-ring and hex
plug; torque to 75 ft-lb (103 N
Sm).
NOTE: Retorque the plug after 5 hours of operation.
Pumping Section
1. Remove the eight capscrews and lockwashers
from the manifold using a 13 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
To avoid damage to the plunger or seals, keep the
manifold properly aligned with the ceramic plungers
when you remove it.
3. Carefully examine each plunger for any scoring or
cracking, and replace as necessary.
Servicing the Plungers
NOTE: Plunger repair kit 801474 is available to
replace retainers, o-rings, washers, and backup rings
for three cylinders.
1. Loosen the plunger retaining screw five to six turns
using a 10 mm wrench. Push the plunger towards
the crankcase to separate the plunger and
retaining screw.
2. Remove the screw from the plunger, and examine
the o-ring, backup ring, and copper bearing/gasket
washer. Replace these parts, if necessary.
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. Otherwise, DO NOT remove these seals
because they cannot be reused. Oil Seal Kit
801473 is available for replacing the seals.
5. Lightly grease the flinger (and the oil seal if it is
being replaced), and replace on the plunger shaft.
Then install the plunger.