when stalactites hanging from your evaporative cooler are 6" long, it has been way too much time between servicings.
always charge electric drill before taking apart cooler
when temperatures inside the house are 10 degrees higher than usual, chances are the pad in your cooler is a solid block of salt.
after you finish servicing and washing out the cooler, the area around your ladder will be ankle deep mud.
do not plug cooler back in while standing in said mud. mud conducts electricity at least as well as water.