Devilbiss GFG-670 plus issue

[1Maynard]

Hi all, first time posting to this forum. Yesterday when I finished spraying some tractor enamel with hardener on a farm tractor I am repainting I was cleaning the gun and noticed quite a bit of paint under the air cap and also around the baffle and behind the nozzle. I have replaced the baffle seal and also the packings for the needle to correct a spitting issue. The gun sprays well and does lay the paint down nice but I do not recall ever seeing paint in these areas before. I torqued the nozzle to 20 ft lbs as recommended on here and also the parts listing. Can anybody give me any idea on why this is happening? I really do not think the paint should be there and I hate to remove the nozzle every time I use the gun. Flushing reducer through the gun will not clean up the paint residue.
Thanks

[Bob K]

Are you sure about 20 ft lbs and should it be 20 inch lbs? I have that gun and the problem you talk about is not one I have ever had. The tip seal as I remember it is a machined taper and the only way I can see for paint to get around it is if the tip was loose at the time you painted or the seal was gauled by over tightening.

As for cleaning I always remove the needle and tip and clean that port with lacquer thinner and a Q-Tip. The needle seal may have been damaged by cured paint left on the needle.

Sorry if I misunderstand your problem but that’s all I can think of for the problem you describe as I understand it.

Bob K

[1Maynard]

Bob K, I double checked on the 20 ft lbs torque and it is correct. I decided to look things over this morning before I used it again and I think I found the problem. The new seal I put on the baffle was not allowing the tip to fully seat on the main body. I mixed some paint and sprayed it and then removed the air cap and the nozzle. I found evidence of leakage between the nozzle and the body where the taper seats. it was only on one side. I recleaned everything even though it looked spotless and put a little gun lube on the baffle seal and reassembled it. Torqued the nozzle to 20 ft lbs and sprayed the white color on the tractor. when I finished I flushed the gun with reducer and dissembled it and it was clean behind the air cap. Problem solved.

[Len]

Bob K, I double checked on the 20 ft lbs torque and it is correct. I decided to look things over this morning before I used it again and I think I found the problem. The new seal I put on the baffle was not allowing the tip to fully seat on the main body. I mixed some paint and sprayed it and then removed the air cap and the nozzle. I found evidence of leakage between the nozzle and the body where the taper seats. it was only on one side. I recleaned everything even though it looked spotless and put a little gun lube on the baffle seal and reassembled it. Torqued the nozzle to 20 ft lbs and sprayed the white color on the tractor. when I finished I flushed the gun with reducer and dissembled it and it was clean behind the air cap. Problem solved.

Remember to never soak the gun body for more than a couple minutes and check out the gun cleaning video at the top of the General Discussion part of this forum.

[1Maynard]

Thanks Len, I never have soaked the gun body for more than a couple of minutes. I am a firm believer in keeping my guns clean. I never had an issue with the plus gun getting paint behind the air cap until yesterday when I sprayed the red color on this tractor. It was the first time I have used the gun since I replaced the baffle seal. I will remember to lube the baffle seal every time I remove the tip to clean. Probably would be a good idea to lube the threads on the tip also. I have viewed the cleaning video.