If the backhoe sits for a period of time, should you grease if you haven't dug with it?
You should grease and exercise it at least monthly. Get that grease circulated around the pins. Cheap insurance against seized pins. That goes for any machine
Grease before parking.
Any advice for dealing with joints where the grease only oozes out from one area and not the entire joint?
Rotate the pin then grease the other side
How do you rotate the pin? Pump pliers? Pipe wrench?
Sorry I should have said rotate on the pin mean cycle the joint - move the boom or bucket which will allow you to grease other places on the pin if you want. I just grease in whatever position is comfortable to get and let go back to work. If you're greasing regularly the pin will be coated. Like an excavator turntable for example. Our Cat's have a grease fitting and a line 180 degrees on the opposite side of the turntable. Grease one side then rotate the house 90 degrees to grease the other quandrants.