DeVilbiss AGGS-522 Operation Manual page 8

E
4.3. Fit new retaining screw (15), disc springs (14), packing piece (13) and needle packing set (12)
over needle (16).
4.4. Insert assembly into Spray Head and screw in retaining screw (15) by hand.
4.5. Remove needle (16) and re-insert from opposite end (See Figure 3).
4.6. Draw needle (16) back until the hexagon key fits into the retaining screw without touching the
end of the needle (See Figure 4).
4.7. Fully tighten retaining screw then back off approximately half a turn – check the needle
movement. The needle should not require excessive force to be moved or be loose – adjust if
necessary.
4.8. Remove needle (16).
4.9. Re-assemble baffle (4, 5 and 6) and fluid tip (3) with new seals as described.
4.10. Re-fit needle (16) in correct orientation.
5. Re-assemble spray head to gun. Check 'O' rings (11) are in position. Engage fluid needle (16) into
piston. Push spray head in and align with location pin, tighten screws (7). Refit air cap and material
hose(s).
TO DISMANTLE GUN BODY, See Figure 1.
Disconnect hoses and release screw (30).
5.1. Remove spray head assembly see steps 1 to 4 and ratchet knob (36).
5.2. Piston (28) and Seals (19, 22 and 29).
5.3. Remove end cap (35) using pin spanner which is part of the accessory tool kit AGG-412.
5.4. Remove springs (32 and 33) and piston (28). Care must be taken when removing the piston
(28) from the gun to ensure that the front forks do not damage the front seal (19).
5.5. Remove the cylinder sleeve (26), accessory tool J-24728 can be used to extract it from the
body.
5.6. Remove the seal and spacer (25), 'O' ring (24), spacer (23) and valve seat (22).
5.7. Using the hexagon key tool provided in the AGG-412 accessory tool kit, remove the seal locking
ring (21), front seal (19) and seal ring (20).
5.8. Fit new front seal (19) into the locking ring (21) and using the hexagon key re-assemble, with
seal ring (20) into body.
5.9. To replace piston seal (29), clamp accessory tool J-24708 into vice jaws, pins upwards. Position
holes in piston (28) onto tool locating pins. Remove piston end cap and seal (29), clean end cap
threads and end of piston. Fit new seal to piston, wipe clean the bore of the cylinder sleeve (26)
and apply a light coating of soft petroleum jelly, remove 'O' ring (27) and replace with a new
one.
Push cylinder sleeve over piston seal (29) ensuring the end of the cylinder sleeve with the
identification groove is pushed on first. Apply one drop of medium strength thread
locking/sealing compound to the threads of the piston end cap and assemble to piston.
Carefully tighten piston end cap, compressing seal (29) until end cap makes contact with the
back face of the piston. Recommended torque: 3.5Nm (30lbf in).
NOTE: This assembly should be left standing upright for 1 hour to allow to compound to
cure.
5.10. Re-assemble valve seat (22) ensuring lip is facing out towards the back of the gun body.
5.11. Re-assemble spacer (23) and 'O' ring (24).
5.12. Remove piston and cylinder sleeve assembly from tool and carefully push seal and spacer (25)
onto piston with lips of seal facing away from cylinder sleeve.
5.13. Fit complete assembly into gun.
5.14. Refit springs (32 and 33), zero sleeve (34) and end cap (35) and tighten down to ensure all
inner components have been securely compressed into position. Recommended torque 21-
24Nm (190-210lbf in).
5.15. Using a screwdriver rotate piston (28) so that forks are facing upwards to allow spray head to be
fitted.
8
© 2007 ITW Finishing Systems and Products