Service - Graco President K Series Instructions-Parts List Manual

Servicing the Air Motor
Before you Start
Be sure you have all necessary parts on hand. Air
Motor Repair Kit 207–385 includes repair parts for
the motor. Pump Repair Kit 239–320 includes
repair parts for the pump. Use all the parts in the
kits for the best results. Parts included in the kits
are marked with asterisks in the text and drawings.
See the parts list and drawing for your pump
(pages 12 to 20) for further information.
Two accessory tools should be used. Padded
pliers, 207–579 is used to grip the trip rod without
damaging its surface. Gauge, 171–818, is used to
ensure the proper clearance between the poppets
and seat of the transfer valve. See Accessories on
page 22 for ordering.
Disassembly
1. Flush the pump. Follow the Pressure Relief
Procedure Warning, at left, before proceeding.
2. Disconnect the air hose from the motor. If
necessary, 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 (F) from the cylinder (G). Pull
up on the cap nut. Grip the trip rod (H) with
padded pliers 207–579 and screw the cap nut off
the trip rod. See Fig 2.
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, 207–579, to grasp the rod.

Service

4. Remove the eight screws (Z) holding the cylinder
(G) to the base (J). Carefully pull the cylinder
straight up off the piston. See Fig 2.
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
(E), to avoid pinching or amputating them. See
Fig 3.
5. Use a screwdriver to push down on the trip rod
yoke (K) and snap the toggle assemblies (E)
down. See Fig 3. Remove the lockwires (L) from
the adjusting nuts (M and Q) of the transfer valves
(N). Screw the top nuts (M) off. Screw the valve
stems (O) out of the grommets (P) and lower
adjusting nuts (Q). Take the valve poppets (R) off
the stems and squeeze them firmly to check for
cracks.
Hold trip rod with
padded pliers
207–579, to prevent
damage to rod
BB
Fig 2
CAUTION
WARNING
H
Z
F
G
J