Trigger valve rebuild on pneumatic framing nailer

I put o-rings in my Dewalt nail gun trigger ad nauseam. Hope this is helpful.

[@jsollien127]

Man o man do I wish I found your video sooner!!! Thank you so much!

[@James-kj8ys]

good video ive been replacing o rings on a hitachi nr 90 ae. trigger assembly i didint see any repair video on this gun anyway i still havent got it right

[@skidog7310]

I'm fixing on the same model. A real pain.

[@dougminnis192]

Very helpful, thanks

[@iankinnon617]

We need a video of how to get to that piece. I can’t remove the smaller pins.

[@kuecker2]

at about 6:04 you point out one of the rings is most important. but you do not indicate which position it is. there are 3 on that piece

[@spudth]

I have to be honest folks, I used a bit of atf as an assembly lube and my trigger quit working. BE ABSOLUTELY SURE TO USE A CORRECT AIR TOOL OIL.

[@b3arwithm3]

Would you have a video how to remove the trigger?

[@spudth]

I don't think so but there's just a pin you push out then the trigger comes right out. I purchased a battery powered metabo HPT nailer. No more compressor, no more air hose. I do miss the larger magazine-20 nails geos real fast.

[@b3arwithm3]

@@spudth yeah battery operated are nice especially for occasional use as we don't need to fire the compressor. They are heavy though.

[@iankinnon617]

@@spudthit’s not just one pin. I got out the first pin easily but I can’t get out the other “spring pins”

[@cdany2000]

Thanks for your video. Where the air was leak? From the front where the nails go out or by the trigger? I have replaced the orings inside but all air exit by the front where the nails go out and no leak by the trigger.

[@spudth]

I did this a long time ago. Basically the white o-rings will decompose. Those are the ones that leak. As far as the trigger, either buy a replacement or get the o-ring kit to rebuild it. The trigger is very sensitive to the kind of lubricant you use.

[@cdany2000]

@@spudth Thanks Chris, unfortunately even if I have replace white o-rings ( was decomposed too ) with a new o-ring rebuild kit, the air flow continue to exit from front. I replaced also the o-ring at the trigger but same issue. When I open the nailer pump, before I close it, I put the piston at front of the cylinder, when I put the air I can listen the piston back and hit the muffler, the air exit from the front where the nails exit. I dont understand why its happend. The seals are new ...

[@josha3833]

You should get head cam to show how you remove-be even more helpful.

[@prieste]

Hi I have a similar nail gun with air leaking where can I buy a O ring set for the trigger valve from please?

[@spudth]

I bought mine from ebay. Search title 'O-Ring Kit for 5140095-73 DeWalt Nailer Nail Gun Trigger Rebuild'. It may be reasonable to just buy a trigger assembly complete as they are very precise and need a certain lube. Also be sure the white o-rings inside are in good shape.

[@lothianmcadam1]

any chance you can reply with the eBay listing number of the trigger seal set you purchased?

[@spudth]

Search this title "O-Ring Kit for 5140095-73 DeWalt Nailer Nail Gun Trigger Rebuild" Remember to choose a correct lubricant as transmission fluid will swell the rubber.

[@JaymeVanAuken]

Extremely helpful my friend I had the same problem took me a little bit to figure out. You hit the nail on the nose. My unit's been packed away in a drawer for about 10 years after thousands of nails and I suspect should have been put away lubricated as well. But I did get several hundred nails through before it went tits up on me. Thank you good instructional video straight to the point.