One of the reasons for paint leaks from spray guns is that the needle packing nut set is not in place or is damaged. Too loose or tightened the screw and hurt seals in the packing nut set are also common causes of paint leaks.
Depending on the construction of spray guns, the location and structure of the needle packing nut vary. There are built-in and external ones.
Our high-end series of paint guns mainly has two kinds of structures. The mainstream design, such as the CFC series belonging to the built-in type, needs to remove and replaced with the help of an Allen wrench. For another patented needle valve integrated structure, the NFC series fit with the external ones, and disassembly and installation are more convenient.
The following disassembly steps and video apply to replace the external packing nut set.
How to replace Needle packing nut set:
Step 1. Screw the needle adjustment knob counterclockwise, pull out the needle and clean it.
Step 2. Hold the trigger, then use a 6mm (1/4”) wrench to turn the screw out counterclockwise
Step 3. Put the new set into the hole, and insert the clean fluid needle. Use a 6mm(1/4”) wrench, turn it clockwise to the end, and then put the needle spring and needle adjusting knob back into the gun body
Step 4. After pulling the trigger back and forth twice, use a wrench and tighten slightly about 1/10th of a turn. Make sure it seals and does not jam the needle.