Graco Fire-Ball 425 205394, Instructions-Parts List Manual

Page: 14 / 20

14 306674U
Air Motor and Throat Service
Reassembly
1. Clean all the parts carefully in a compatible solvent
and inspect for wear or damage. Use all the repair
kit parts during reassembly and replace other parts
as necessary.
2. Check the polished surfaces of the piston, piston
rod and cylinder wall for scratches or wear. A
scored rod will cause premature packing wear and
leaking.
3. Lubricate all parts with a light, waterproof grease.
4. Be sure the o-rings are in place. Slide the piston
rod down through the throat bearing and lower the
piston (5) into the air motor base (56).
5. Pull the exhaust valve poppets (38*) into the valve
actuator (13) and clip off the top part shown with
dotted lines. See Fig. 5.
6. Install the transfer valve poppets (37*) onto the
valve stems (30*), then reassemble the valve
stems (30*), bottom adjusting nuts (27*), grom-
mets (18*), and top adjusting nuts (27*) on the
piston (5). Assemble the trip rod (1), valve actuator
(13), trip rod yoke (14) and toggle assemblies (K)
on the piston. See Fig. 5.
7. Before installing the lockwires (28*) in the adjusting
nuts (27*), use the special gauge 171818 to adjust
the transfer valve (M) so there is 0.125 in.
(3.68 mm) clearance between the poppets (37*)
and the piston (5) when the toggle assemblies are
in the down position. See Fig. 5.
8. Snap the toggle assemblies (K) to the up position.
Reinstall the cylinder (32) and cap nut (31). Reas-
semble the air motor to the displacement pump.
9. Before remounting the pump, connect an air hose
and run the pump slowly, at about 40 psi
(0.28 MPa, 2.8 bar) to ensure that it operates
smoothly.
10. Reconnect the ground wire before regular opera-
tion of the pump.
Throat Packing Service
The piston in the air motor, located behind the air
motor plates, moves when air is supplied to the
motor. Moving parts can pinch or amputate your
fingers or other body parts. Therefore, never
operate the pump with the air motor plates
removed.
WARNING
See Fig. 6 on page 15 and the parts drawing and list
(pages 16 and 17) for further information.
1. Clamp the pump in a vise and unscrew the riser
tube (80) from the air motor base (56). Pull the
riser tube away from the air motor until the cotter
pin (60
}
) which secures the displacement pump
connecting rod to the air motor piston rod (52) is
visible. See Fig. 6.
2. Remove the cotter pin (60
}
) and unscrew the
pump connecting rod (79) from the air motor piston
rod (52). See Fig. 6. Remove the cylinder (32)
from the air motor base (56) as described under
Disassembly on page 12.
3. Remove one louvered air exhaust plate (36) and
unscrew the throat packing nut (45
{
), using a
spanner wrench or a 0.22 in. (5.6 mm) diameter
rod. See Fig. 6.
4. Remove the packing nut (45
{
), male and female
glands (47
{
, 48
{
), v-packings (49
{
), washer
(44
{
), bearing (46
{
), retainer (24
{
), wiper (22
{
),
o-ring (23
{
), u-cup (25
{
), and washer (26
{
) from
the base.
5. Clean the throat packing area in the base and the
packing nut. Clean and inspect all parts, and
replace as necessary.
6. Lubricate the packings, piston rod and piston
flange with a light waterproof grease.
7. Install the washer (26
{
) into the base. Assemble
the packing (25
{
) and the wiper (22
{
) into the
retainer (24
{
). Install the o-ring (23
{
) onto the
retainer, and insert the retainer assembly into the
base.
NOTE: Make sure the packing (25
{
) lips face
down, and make sure the wiper (22
{
) lips face up.
8. Insert the bearing (46
{
) and the washer (44
{
) into
the base. Assemble the female gland (48
{
),
v-packings (49
{
), and the male gland (47
{
) into
the packing nut (45
{
).