MVP ATC-4000 Series, Repair Manual

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ATC Chopper Gun Operations Manual
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14. Reinstall the catalyst cylinder into the gun head by rotating it back and forth while pushing it
into the gun head, making sure not to damage the O-rings and to align the hole in the
catalyst cylinder with the hole in the side of the gun head.
15. Replace the set screws back into the gun head.
Note The hole in the catalyst cylinder has to line up with the hole in the gun head so
that the set screw may be reinstalled. If the screw does not go in fully you may
need to realign the catalyst cylinder.
16. Using a
5
16
nut driver, remove the diffuser seat from
the front of the gun.
17. Using special tool ATC-40323-BT, remove the
cartridge assembly from the front of the gun.
18. Pull the resin needle piston assembly from the back of
the gun head.
19. Replace the O-ring on the resin needle piston.
20. Remove the packing retainer from the back of the gun head and replace the O-ring with a
new one.
21. Replace the packing retainer back into the back of the gun head.
22. Replace the O-ring for the resin cylinder seal.
23. Replace the two tip pin O-rings on the front of the gun.
24. Remove the catalyst cylinder plug on the front of the gun head and replace the O-ring.
25. Reinstall the catalyst cylinder plug into the front of the gun head.
26. Replace the O-ring on the diffuser seat.
27. Using a pin and wrench, loosen the needle packing housing from the packing retainer.
28. Check that the packing press moves freely in the packing housing and clean as necessary.
29. Replace the two packings in the packing housing.
30. Hand tighten the packing housing, packing press, and two packings together with the
packing retainer.
Note Use caution not to overtighten the packing retainer into the packing housing.
The resin needle will not go through the packing if it is too tight.
31. Tighten the lock nut to secure the packing housing.