Graco Inc Serles A, 800-903, 800-902 Pump Service, Servicing the Plungers, Valves, Pumping Section

PUMP SERVICE

To reduce the

Servicing the Plungers

P/N803-677is availableto

risk of

serious bodily

injury,

NOTE Plunger repair kit,

including fluid injection, splashingthe eyes or replace retainers,

O-rings. washers

and

on the skin, or injury from moving parts, always backup rings for three cylinders.

-

follow the Pressure ReliefProcedureWarnlng

before proceeding.

1 .

Loosen the plunger retaining screwtofivesix tums,

NOTE

The following metricwrenches are needed:

usinganMlOwrench.Push theplungertowards the

crankcase to separate the plunger and retaining

M10, M13 and M30. Repairkits are available.

screw.

Referto the individual repair sectionsandthe

2.

Remove the screw fromihe plunger and examine

pagefor more details. For thebest

pump parts

the O-ring, backup ring and copper bearing/gasket

results, useall parts in the kits.

washer. Replace these parts,ifnecessary, usingkit

NOTE: There are

Wo different tool kits to aid in

801-474.

servicing the pump. P/N800-298is used to

3. Remove the plunger and flinger from the plunger

ease installation of packings. P/N 800-271

shaft. Clean, examine

and replace parts as

includes

the itemsin800-298andtoolsto aid

necessary.

in the removalof packing retainers.

4. Inspect the plunger shaft foroil leakage from the

Valves

crankcase. If leaking is

obvious, replace

theoil

NOTE: For a set of six valves, order P/N803-664or

seals. Otherwise,DO NOT remove these sealsas

they cannotbe reused.An oil

seal

kitis availableto

1.

803-666.

replace

the seals.

Remove the hex plug

fromthe manifoldusing an

5.

Lightly

grease theoil seal, if

it is

being replaced,

2.

M30 wrench.

and the flinger and replace them on the plunger

Examine the O-ring under the hexplug and replace

shaft. Theninstall the plunger.

it if it is cut or distorted.

6. Lightly grease the retaining screw and the outer end

3. Remove the valve assembly from the cavity; the

oiihephger. Place the wisher,O-ring and backup

ring around the screw and install the screw through

assembly may come apart.

the plunger. Torqueto 14.4ft-lb(19.5 Nm).

4.

NOTE: Retorque the plug after 5 hours of

operation.

7. Lubricate. the outside of each plunger. Slide the

Pumping Section

manifold onto the crankcase, being careful tonot

damage the seals.

1. Remove the eight capscrews and lockwashers from

8. Install the capscrews and washers finger-tight.

the manifold using anM13 wrench.

Carefully separate the manifold from the crankcase.

Torquethescrewsto21.7ft-lb(29Nm)followingthe

2.

tightening pattern (Figure4). Uneven tightening

NOTE:

It maybenecessaryto tap themanifold lightly

may cause the manifoldto bind or jam.

with asoft mallet to loosen.

CAUTION

I

Keep the manifold properly aligned with the ceramic plungers when removing to avoid damage to the plungeror seals.

3.Carefully examine each plunger for any scoring or cracking and replace as necessary.

Figure 4

10308-533