Dug out my old roofing nailer for the first time in 6 years and shot a half dozen nails thru it and it worked just fine. Decided to give her a few drops of oil so I grabbed the WD40 can and give it a shot down the air inlet. Took it back over to a test board and shot another half dozen nails and everything was ok until it started leaking air out the trigger. Wasn't long and it just got worse until the leak was way out of control.
Took the nailer apart and started cleaning and inspecting some parts, the botton O ring was swollen so bad in the trigger assembly it was hard to get apart. I'm not sure what caused the O ring to swell or if that is the problem but I'll never use WD40 in another nail gun. Ordered a new trigger, so only time will tell if the swollen O ring is the problem or not.
Took the nailer apart and started cleaning and inspecting some parts, the botton O ring was swollen so bad in the trigger assembly it was hard to get apart. I'm not sure what caused the O ring to swell or if that is the problem but I'll never use WD40 in another nail gun. Ordered a new trigger, so only time will tell if the swollen O ring is the problem or not.