i have a leak from my 2002 jeep grand cherokee 4 x 4 from what i believe is the water pump. it is a drop every 10 seconds or so and continues after being turned off even after it sits for a long time and the radiator cap has been removed (if that relieves pressure). i have zero problems with overheating even when i forget to refill it for several days. Do i need to replace the water pump or just the seal or what? can i just let the coolant drain out by unclamping the hose from the pump housing? thank you very much for any help.