by Alan » Thu May 18, 2017 6:10 pm
Had the same problem myself. The solution is to let the air out. To do that, once you've got a grease cartridge installed, you set the grease gun upright with its handle downward against the surface of a workbench. Pump the handle while maintaining downward pressure on the grease gun (to produce upward pressure on the handle).
At the same time, release the air. There might be a fitting at the hose end of the gun with a spring-loaded ball - if so, push in on the ball, using your third hand, while pumping the handle.
If there isn't a fitting, unscrew the cap slightly so air can escape, then pump the handle while maintaining downward pressure on the gun. This method only takes two hands. Once the air is out, tighten the cap.
Something else I learned through experience: When you fit the hose (or tube) over the Zerk fitting (aka grease nipple) on the axle, unscrew the fitting on the end of the hose (or tube) slightly, then press it onto the Zerk fitting until it clicks, then tighten the fitting on the end of the hose (or tube). Pump grease as needed, then unscrew the fitting on the end of the hose (or tube) before you try to pull it off of the Zerk fitting. If you try to muscle it off without loosening it, the Zerk fitting will break off.