I tested it in my driveway before I might really need it. The first issue that I had was that the manual said to remove a sticker from the end of the pump and insert a hex bit. However, the way my pump was mounted there was less than 2 inches to a wall. After two hours rotating the pump, two of the bolts were out of sight and had to be done by feel, I finally had it aligned at an angle that allowed me to try it. It worked fine especially if, as was mentioned, you close the valves, if available, and do one slide at a time. The key is to try it when it is convenient not at night in a campground in the middle of a rainstorm which would be my luck.