97 3.0 overheating need help quick!

The van started overheating today while my mom was driving it. I drove it home and tried to figure out what the problem could be. I don't think it's the thermostat because I checked the upper radiator hose to see if it was hot like the Haynes Manual says and it was. The radiator cap felt warm but not extremely hot while the van was on. it did get hot once the engine was turned off. I'm not sure if it could be the water pump since it was replaced last year and so was the temperature sending unit, by the way where is it located? I thought there would be a hose going to it but I couldn't see it.My mom did say that coolant was overflowing from the resevoir, it must've leaked a lot of coolant because the resevoir was just empty when I saw. I did fill it up then let the engine run, once the temp started to climb aove normal it started to overflow. Both fans are coming on at about the halfway point. What are the characteristics of a faulty water pump or radiator? I'm thinking its either one but I don't want to be guessing at what it could and find out that its not that. Any suggestions?

could be that the rad is plugged and not providing the cooling as required or could be head gasket(s).How is the van running, any white smoke out the back?Has the rad been flushed ever?I would start with the rad and work from there.And how many miles on the van?

The van has almost 82,000 miles, theres no white smoke coming out and the van is running fine except for the overheating. The water pump was changed out about a year ago so I'm sure the coolant had to be drained to replace it. Should I just try flushing it or should I replace it?

If both fans are coming on it can only be a few things , either the radiator core is plugged which would be unusual if it has seen regular flushings at every 30K or so , or it could still be a thermostat that is not opening up all the way and restricting coolant flow . Does the coolant under the radiator cap look dirty or rusty ? Should be a fairly bright green if its still in good condition . Also get a coolant checker and see what the boiling point of the installed coolant is , if its weak then the boiling point will be a lot lower . Also another thing to check is is the timing ok , if it slipped a tooth then it will run a lot hotter also , was the timing belt changed when you did the water pump ?? If not it could be something like that , though you should be able to tell if it did that as performance would be real sluggish and not run right..

when the fluid in the overflow tank over flows, along with a steady stream of air bubbles, its an indication that you have a blown head gasket. This happened to my brother's 97 Venture, his head gasket was blown at the number two cylinder, letting the air in the combustion chamber to push its way into the cooling system and eventually into the rad and out the overflow tank. With his van it was easy to diagnose as there was anti freeze all over the number 2 spark plug. You may want to have a compresion check done and or have the cooling system pressure tested to confirm it either way.

I took out the thermostat and it was broken. I changed it out and replaced it with a 180* thermostat and put a gallon of coolant in. I let the van run for awhile and its not overheating now.

I took out the thermostat and it was broken. I changed it out and replaced it with a 180* thermostat and put a gallon of coolant in. I let the van run for awhile and its not overheating now.
I hope you did not put in straight coolant , that is a no no . It has to be mixed with water unless you bought the stuff that was premixed . It should be 50/50 for maximum protection and heat transfer...

Yes it was 50/50 premix and I also added some water.