95 3.4L Overheating... I need help!

My 95 camaro has been notorious for overheating off & on the past couple months. I've read through the forums for some more help but I didn't get exactly what I was looking for so: First time it happened I found the water pump was leaking so we changed that and it hasn't leaked since. I also switched to a fail-safe thermostat. Now it's overheating and when it does the coolant/water actually boils out of the reservoir. It's happened three times and I've been checking with people and my Haynes book to see what's the problem but I thought somebody here might be able to help.

Radiator is pretty dirty/rusty so I ordered another and it should be here tuesday (7/19).
Radiator fan (is this also called Blower Fan?) doesn't seem to be kicking on. It seems everywhere I've read has a different temp. of when the fan is supposed to kick on. But if it isn't turning on when the coolant is actually at a boil, then I know something's wrong.
I'm not sure if the coolant sensor that actually makes the fan turn on is working, I guess I'll find that out once I check the motor? I've read that maybe I should touch two wires to the battery and the radiator fan motor and see if it turns on. (Is this hard to do?????) I've also read to get a voltometer and check the relay or just go ahead and buy a new one.

My question's are: Am I going about this the right way? Should I check the radiator fan first w/ the wires & battery? Or is there a better way to do this... I've read somewhere that if I turn the A/C on then the fan should come on automatically but when I did that, it still didn't come on at all. Coolant level is full, by the way. Should I then replace the coolant sensor if the motor and relay are working fine?

Any help would be appreciated!
Justin (nicholson82@hotmail.com)

EDIT: Just a little bit more information. It only overheats at idle when I've been parked for a little bit. I've flushed the radiator at least 5 times and it's still rusty inside. I've also ran it 85% water and 15% coolant and a bottle of "Water Wetter" to make it run cooler and it still overheats.

its hard to say if you radiator is extreamly rust and nast on the inside I could sugest replacing it. It could be clouged and now flowing and cooling properly. And what do you mean by a fail safe thermostat? As far as the fans not comming on I would first check the relay if you are in doubt that they are bad just replace them. They are extreamly cheap and not hard to replace. The first fan should kick on around 200 and I blieve the second one should kick on around 220. How are you determining that the car is over heating are you listining for the coolant to boil while the engine is running or are you watching the temp gage on the intrament pannel? It could be alot of things you are just going to have to eliminate them one by one until it stops overheating.

Runing too much water over antifreeze in the radiator will just rust it up again. Whatever you do, don't run all water.

Your fans not coming on? check your relay and fuses as well as the coolant temp sensor.

Hook a fused wire to the battery and test your fans by putting the ends in the connector.

Did you change your hoses when you did the water pump?

A collapsed hose could cause the problem,it will look fine but collapse when the water pump starts pumping.

you might want to get your radiator reversed flushed also..

Your fans not coming on? check your relay and fuses as well as the coolant temp sensor.

Hook a fused wire to the battery and test your fans by putting the ends in the connector.

Did you change your hoses when you did the water pump?

A collapsed hose could cause the problem,it will look fine but collapse when the water pump starts pumping.

Checked all the fuses, we're waiting until wednesday to get a voltometer to check the relay.
By fail-safe I mean that if the thermostat did in fact fail, it would lock open instead of locking closed. So if my car ever runs super-cool then I know the thermostat has failed and needs replacing. Better than closed and not being able to drive.

I know the car's overheating by the instrument panel and by the fact I can hear the coolant/water boiling in the radiator and overflowing from the reservoir.

We didn't change the hoses, we'll probably do that when we change the radiator wednesday. Are they expensive? I suppose we're going to check the fan first. We checked prices for fans and most were about $25.
How/Where do you get fused wires??

Thanks for everybody who's replied so far.

you might want to get your radiator reversed flushed also..

We're just gonna go ahead and replace the radiator. It's rusted inside and everytime I drain it, the coolant is an orange-brown.

You can buy an inline fuse at any auto parts store,just add more wire to make it reach.

Fan Motor was burnt out, Radiator still needing replacing. So I replaced both and now it's running really smooth, air conditioning works better than ever. Thanks for everyone's help!