Zerk Zapper Grease Fitting Cleaner. We'll see if it can get the one fitting in the front end that won't take grease. I got the version that has interchangeable pistons - typical hammer strike piston and air-hammer adapter. I'm going to try the gentler approach before going to the air tool. I like this model - made in USA, and double o-ringed - which is why I got it, not so much the air hammer adapter.
