I noticed a very tiny fluid lead under my cavalier. It slowly got worse, then evaporate. (at first it was very oily feeling) Everything seemed fine as long as I replaced the fluid accordingly. The temp. was always fine. Limited to repair possibilities. I irresponsibly kept driving it. I filled it too full twice, because it started leaking so fast. That was bad, and the car started to get hot for the first time. I stopped and slowly released the R. cap to release pressure and let fluid run out a little. As long as I have the air on and I'm accelerating. The temp. stayed fine.(by now you know I'm an idiot.) The next time I drove it, nothing I did stopped it from getting WAY hot. That IS THE LAST TIME I'VE DRIVIN IT. I've priced both a radiator and a water pump. I think I like the water pump scenario the best. If it is the radiator. Getting one from a junk yard would be counter productive if it's the same year car wouldn't it? Or would that be O.K. if it was from one that was only actually driven for a small amount of miles for one reason or another. Then rendered lame for parts? I did have a friend look at it. And after the engine and what not dried from me filling resivour. He notice a little rust stain where the water pump it, then the leak. I hope my question is explained well. thank you

Sounds like it is the water pump, but to be sure, I would fill the radiator and reservoir with water (save the coolant for later when it's fixed) start up the car, let it run until it warms up, turn off and carefully check for leaks. Make sure you don't touch hot surfaces, and you can buy a small mirror at a parts store to help look in difficult tight spots. Make sure everything is dry before you start(especially around the water pump and radiator), that will make your 'detective ' work easier. If you're still not sure where it's leaking, repeat the above steps AFTER the car has cooled down so you can safely open the radiator cap. You will not harm the car doing this as described. If it turns out to be the radiator, you can remove it and bring to a radiator shop for repair (better than purchasing a used one). Get a couple of prices 1st. And YES, you explained it very well! GOOD LUCK countrycurt0

Well cavalier waterpumps do leeak, get a mirror and look under the waterpump for a stain from the hole under it behind the pulley on the bottom if there is antifreeze or a stain change the waterpump, BUT first if you can I would make sure you did not blow the HEADGASKET take out all the spark plugs, connect a cooling system pressure tester to the radiator or coolant bottle pump up the pressure to about 25psi and look for leaks if you have a leak you may bave to fix it to proceed then keep the pressure pumped up and make sure the coolant is full before you begin and let it stay ther for about 1 1/2 - 2 hours watching in the spark plug holes for any evidence of antifreeze leaking in if so your head and or headgasket are bad.
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