How do I know if the water pump is bad
 

How do I know the water pump is bad. Are there ways that I can test to see if it is still working or not. I lose alot of coolant. Its not leaking outside and there is only a little bit of white smoke from the tailpipes. When I start it, it takes a long time to heat up but the needle just keeps on going up until it overheats. There isn't anything blocking the radiator. I know the smoke means that I probably overheated and blew a head gasket. But I don't want to replace the gasket and have it blown again cause the pump isn't working. It the chicken and egg problem.
Can anybody help me out with this.

I might replace the thermostat first with a 180 degree stat. If your waterpump is not leaking and it turns freely it is usually good.

The thermostat is a new one but its 195. I have a 180 but I was going to wait until my emissions inspection to put it in.

easyest way to do it is to let the car sit and warm up with the rad cap off and once the car hits 180* the thermostat should open and you should see water flowing out of the top fins empting into the rdiator..this will tell you that both things are working..water pump doesnt usally stop wokring..the seal goes and it leaks

One thing I forgot - maybe the radiator cap is not sealing to allow the normal presure buildup inside the radiator. This can also cause a car to heat up.

grab fan blades on opposing sides. if you can move the fan side to side, replace the pump. if not, you have another problem.

Take the cap off and see if there are tiny air bubbles in the radiator and also pull the dipstick. If the dip stick is milky that is a sure sign of a blown head gasket. A bad water pump will pump water out where ever it can. Is there a puddle of coolant under the car when you park?
A milky dip stick will definatly indicate a blown head gasket though. If you have to replace either one of those then I would also throw on that new cap you have.

If you have white smoke your going to HAVE to replace either your intake and/or head gaskets so you will have a lot of the front end bracketry unhooked anyways. Pull the waterpump off at the same time and check it out. If the bearings, seals and impeller ar still o.k you can re-use it. Do not run your engine with coolant in the lubrication system or you will be doing bearings and possibly worse (can cause pitting in the crank, cam, etc... ).