Stuck Grease Gun on Grease Nipple. Need help removing it.

[IslandTractor]

It gets stuck because the pin / bushing is clogged. It will continue to get stuck until you clear out the built up gunk. You can try solvent and wiggling the pin, driving it back and forth. There is also a grease gun like device that injects high pressure solvent to break up the clog.quote]

I have one of those zerk rejuvinator maintenance tools. Works quite well. I got it either from Northern Tools or HF. You just load up the cylinder with light oil, attach it to the zerk just like a grease gun, then hit the head with a mallet. It shoots the light oil into the zerk under high pressure and most of the time clears the clog. You can then just grease normally. The few times it hasn't worked I've pulled the zerk and found impacted dirt inside the fitting. (from poorly protected zerks at the bottom of a 4n1 bucket).

 

[irwin]

A month or so ago I had two fittings that wouldn't take grease. I have several size's of zerks on hand so replaced them...still no good.
One was a loader joint, I just removed the pin and cleaned out the little grease passage hole (it was so packed I had a hard time finding it)..cleaned the joint parts and put grease on the pin and in the bushing..back together and it then took grease fine..
The other problem joint was the lower swing arm pin on my backhoe...no room to try easily so I bought a 90' adapter and tried my new tool "Grease Joint Rejuvenator Cleaning Tool " but that passage and bushing was packed solid too and had no luck with the tool. I ended up removing the zerk and bent a piece of electric fence wire..fed the wire in the zerk hole and down the pasaage and felt around for the small hole. I dug a bit of something that felt like dried valve lapping compound/crud out. Then I hit it with a MAP gas torch, put the zerk back in and moved the joint around and I thought my gun was out of grease cause it quit complaining...but no it was finally working.

The first picture is the dry joint,( lower swing arm ) second pic is the grease oozing out around the joint.