Hey Dun,
Whatcha think I am some dumb Hillbilly from the Ozarks? I's a dern smart Hillbilly from Georgia, near Atlanta where the smarts come from.
I pressed all the doohickeys and release all the air, nada.
I took each part off and checked. Finally, I took the tip (where it attaches to the zerk, not the jerk) off and there is a ball bearing in there - I took it out and cleaned it and put it back - it worked once. I repeated it again and it has worked fine since. This Ingersall thingy is different from the other grease gun I have. Once you pull the trigger it continues to bang , bang, bang grease out. The other one you had to pull each time you wanted a bang of grease.
Hope this helps someone else.
See, we Georgia Hillbillys aren't as stupid as we look.
Billy