Graco Series D, Instructions And Parts List

Page: 15 / 24

Repair
308608L 15
Reassembly
Ensure that all necessary parts are on hand. Air Motor
Repair Kit 207385 includes repair parts for the motor.
For best results, use all of the parts in the kit. Parts
included in the kit are marked with an asterisk in the
text and drawings, for example (19*). See Parts List ,
page 19.
1. Place the piston rod (29) flats in the vise with the air
motor facing up.
2. Pull the exhaust valve poppets (26*) into the valve
actuator (12), and clip off the top parts of the
poppets (shown with dotted lines in the Cutaway
View in F
IG
. 4).
3. Install the grommets (17*) in the actuator (12), place
the inlet valve poppets (32*) in the piston, and
thread the bottom valve nuts (21*) onto the inlet
valve poppets until there are a few threads left
before the threads run out.
NOTE: If the valve nuts are threaded too far down onto
the poppets, they will run off of the threaded part of the
poppets.
4. Grease heavily and place the trip rod (31) in the
piston, place the actuator (12) in the yoke (13), and
place the well-greased actuator/yoke assembly in
the piston, with the trip rod going through the
center holes of the actuator and yoke and the inlet
valve poppets (32*) going through the grommets
(17*).
5. Thread the top valve nuts (21*) onto the inlet valve
poppets (32*) until one thread of the inlet valve
poppets is exposed above the valve nuts.
6. Install the toggle pins (15) in the yoke (13), place the
toggle arm (23) ends of the toggle assembly (M)
onto the toggle pins, and snap the pivot pin (16)
ends of the toggle assembly into the lugs (L).
7. Measuring with the gauge (Part No. 171818), create
0.125 in. (3.18 mm) of clearance between the inlet
valve poppets (32*) and the piston seat when the
inlet valve is open. See the Cutaway View in F
IG
. 4.
NOTE: Adjust the distance between the inlet valve
poppets and the piston seat by turning the top valve
nuts (21*).
8. Hand-tighten the bottom valve nuts (21*) securely.
9. Align the holes in the valve nuts (21*) and the slots
on the top of the inlet valve poppets (32*), and drop
the lock wires (22*) through the holes in the valve
nuts and into the slots in the inlet valve poppets.
Pull the lock wires down tightly, and bend the ends
with pliers so that they cannot be pulled back out of
the holes.
10. Grease and install the new o-rings (19*, 20*) on the
piston assembly (27) and in the groove in the air
motor base (28).
11. Clamp the air motor base (28) in a vise horizontally
by closing the vise jaws on the flange.
12. Grease and reinstall the u-cup seal (10†), thread
and throat bearing (36) into the air motor base (28),
and torque the throat bearing to 30 to 40 ft.-lbs
(40.7 to 54.2 N•m) using a 2 in. socket.
13. Slide the piston rod (29) down through the packing,
and lower the piston assembly (27) into the air
motor base (28).
14. Carefully lower the cylinder (30) straight down onto
the piston assembly (27). Tighten the eight screws
(3) holding the cylinder to the base (28).
15. Grip the trip rod (31) with padded pliers, screw the
lift ring (24) onto the tip rod, push the lift ring down,
and screw it into the top of the cylinder.
16. Install the u-cup packing (107†) with the lips facing
up, and place the piston washer (113) on the
piston/valve sear (109). Make sure that the lips of
the u-cup packing face up (F
IG
. 3)
17. Place the piston ball (103) in the piston rod (29).
18. Clean the threads of the piston/valve seat. Apply
thread locking compound to the threads (109), and
thread the assembly from step 16 onto the piston
rod (29).
NOTICE
Do not reuse the old lock wires. They become brittle
and break from too much bending.
NOTICE
To avoid damaging the cylinder wall, lower the
cylinder straight down onto the piston. Never tilt the
cylinder as it is being lowered.