When disassembling a brake valve it's not uncommon to find an internal component that can't be easily pulled or pushed out using mechanical pressure. Heat from a propane torch coupled with compressed air sometimes works, but when can you do when compressed air doesn't get the job done, either? I've found that using hydraulic pressure will typically do the trick, and it's relatively easy to apply hydraulic pressure using a common grease gun. The challenge is connecting your grease gun to the ports on your brake valve. How can it be done?