There are some very obvious ways to tell if your water pump is bad, aside from simple overheating
. Sometimes the pulley on the front of the water pump will just shear right off. That's a bad pump. Other times it's more subtle, but there are still signs. If everything else seems to be functioning well in your cooling system, start paying attention to your water pump. The first sign that your water pump will fail you soon is called weeping. Water pumps are designed so that when the bearings inside start to fail, the seal begins to weep, allowing small drops of coolant to leak out. This is intentional, and those drops under your car are meant to warn you that your water pump isn't going to last much longer. It's also important to listen to your water pump. You shouldn't be able to hear it. If you hear rubbing, grinding, whining or other noises coming from the area of the pump, that's a sign that the bearings inside might be failing.
If you need to replace your water pump, read on and I'll help you figure it all out.