If material leaks from around or through the packing nut, readjust the packing nut.
1: Disconnect the air hose from the air inlet and remove the cup assembly.
2: Pull the trigger all the way back and hold.
3: Tighten the packing nut using a 3/8” wrench until the needle remains retracted inside the nozzle when you release the trigger.
4: Loosen the packing nut slowly until the needle moves freely back into position in the nozzle.
Once you have adjusted the nut, reconnect the air hose and the cup assembly. Squeeze the trigger to see if the leaking has stopped. If it has not, make sure the packing nut is a tight as possible, while allowing the needle to move freely. If adjusting the packing nut does not sop the leak, replace the packing.