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

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12 306674U
Air Motor and Throat Service
Before you Start
D
Be sure you have all necessary parts on hand. Air
Motor Repair Kit 207385 includes repair parts for
the motor. Pump Repair Kit 239320 includes repair
parts for the pump and the air motor throat area.
Use all the parts in the kits for the best results.
Parts included in the kits are marked with an aster-
isk (*), a dagger (
{
), or a double dagger (
}
) in text
and drawings. See the parts drawing and list
(pages 16 and 17) for further information.
D
Two accessory tools should be used. Padded
pliers, 207579 is used to grip the trip rod without
damaging its surface. Gauge, 171818, is used to
ensure the proper clearance between the poppets
and seat of the transfer valve.
Disassembly
1. Flush the pump. Follow the Pressure Relief
Procedure Warning, at left, before proceeding.
2. Disconnect the air hose from the motor. If neces-
sary, disconnect the motor from the pump. Clamp
the air motor base in a vise.
3. Manually push up on the piston rod to move the
piston assembly to the top of its stroke. Unscrew
the cylinder cap nut (31) from the cylinder (32).
Pull up on the cap nut. Grip the trip rod (1) with
padded pliers 207579 and screw the cap nut off
the trip rod. See Fig. 4.
CAUTION
Do not damage the plated surface of the trip rod.
Damaging the surface of the trip rod can result in
erratic air motor operation. Use the special padded
pliers, 207579, to grasp the rod.
4. Remove the eight screws (7) holding the cylinder
(32) to the base (56). Carefully pull the cylinder
straight up off the piston. See Fig. 4.
CAUTION
To avoid damaging the cylinder wall, ALWAYS lift the
cylinder straight up off of the piston. Never tilt the
cylinder as it is being removed.
Always keep fingers clear of the toggle assemblies
(K), to avoid pinching or amputating them. See
Fig. 5.
WARNING
5. Use a screwdriver to push down on the trip rod
yoke (14) and snap the toggle assemblies (K)
down. See Fig. 5. Remove the lockwires (28*)
from the adjusting nuts (27*) of the transfer valves
(M). Screw the top adjusting nuts (27*) off. Screw
the valve stems (30*) out of the grommets (18*)
and lower adjusting nuts (27*). Take the valve
poppets (37*) off the stems and squeeze them
firmly to check for cracks.
Fig. 4
32
7
56
36
1
Hold trip rod with
padded pliers
207579, to prevent
damage to rod
31