The oil and coolant have to be drained to take the clutch cover off which is required to take off the water pump. If the extra cost of a new pump over the time and, possibly, tools it takes to disassemble the old pump and replace the seals is worth it to you, replacing the entire pump is a fine idea. You'll need a new clutch cover gasket in any case. See http://www.stromtrooper.com/v-strom...ck-labs-2011-bike-modification-thread-21.html for details on rebuilding and replacing a water pump.