Knowing How to fill a grease gun is essential for proper maintenance. First, ensure the gun is clean and free of old grease. Release the pressure by pulling the trigger. Remove the grease cartridge or open the filler port. If using a cartridge, slide it into the chamber and secure it. For bulk filling, load grease directly into the port using a grease pump. After filling, reassemble t... https://www.micro-lube.com/product/color-coded-grease-gun-pistol-grip/