In addition to using air, I made a water wand too. I picked up a garden hose wand, with the sprinkler head and a shut off valve on the hand grip. I cut the head off but left part of the crook in the end of the aluminum tube. Then I pinched the cut end closed and bent it some, so it sprays a fan shaped blast of water at nearly 90* to the shaft. It works really well to sneak it in from the back side of the radiator and between fan blades.