that black or red plastic bolt on the pump comes off,count the number of turns it takes to remove it.
under it you will see a series of plastic disks that should be checked for wear,i shoot some brake cleaner in the hole and lube with some 30# oil after it dries
reinstall the plastic nut the number of turns they took to remove,you may need to adjust them after cleaning
the other thing is the threads on the top bracket clamps tend to strip over time and the arms can be hard to swing,couple of drops of oil on all the pivot points help
check the holes on the flanges that you attach to the roof,long term use causes the holes to widen and could possibly allow the fastener head to pull thru,i usually drill extra holes in them anyway so i don't need to reposition them if the screw happens to fall in a board seam