Graco GX-8 Operation, Parts, Service, Repair page 20

d. Use 3/8 in. wrench on hex-shaped valv-
ing rod shank and 1/2 in. wrench on jam
nut.
e. Loosen jam nut and back it away from
valving rod shank by 3 or 4 full turns.
f. Unthread valving rod and jam nut from
piston shaft.
5. OPEN safety stop.
6. Use 9/64 in. ball point hex key to remove
socket head cap screw that holds air cylin-
der to handle (F
IG
7. Use retaining ring 45° pliers to remove
retaining ring that holds end cap in place
inside air cylinder.
8. Remove end cap/safety stop assembly and
piston spring:
a. Pull safety stop and attached end cap
out of air cylinder.
b. Remove piston spring located inside
cylinder. Be sure to retain spring for
reinstallation.
Force will be required to remove end cap
because ring is tightly compressed.
9. Inspect end cap ring. Replace if damaged.
Apply light coating of Lubriplate grease and
install new end cap ring.
Skip steps 11-13 and go to step 14 if only
end cap ring and cup seal need to be
replaced.
20
. 16).
a. Remove piston/rod assembly:
Use gun block mounting screw (screw
that holds gun block to bracket) to aid in
removal of piston.
b. Look into rear of air cylinder and thread
mounting screw into center hole of pis-
ton at least 4 full turns.
c. Use 6 in. pliers to grab mounting screw
and pull piston rod assembly out of air
cylinder.
d. Inspect ring and replace if damaged.
Apply light coat of Lubriplate grease
and install new ring.
10. Inspect air cylinder cup seal. If air escapes
around piston rod during operation, remove
and replace cup seal located in front of air
cylinder. Lubricate new cup seal with
Lubriplate grease and install it. Make sure
cup faces toward rear of cylinder.
11. Insert piston and rod assembly into air cyl-
inder. Be careful not to damage cup seal in
front face of air cylinder as rod passed
though. Remove gun block mounting screw
from piston.
12. Disassemble safety stop mechanism:
a. Use 5/64 in. hex key to remove two set
screws from knob.
b. Slide knob off stop pin and retain stop
pin spring.
c. Pull shaft out of end cap (F
13. Remove cup seal from end cap and inspect
for damage. Remove if damaged. Apply
light coat of Lubriplate grease and install
new end cap ring.
Repair
. 17).
IG
311338B