Car started over-heating on the way to class. Made it safe to class, and finally found time to pull vehicle into shop and get it up in a lift. Pulled radiator outlet hose from where it connects to engine at thermostat housing, and found bad thermostat. Pulled and replaced thermostat, refilled with coolant, and attempted to drive home. No such luck, didn't even get out of the parking lot. Pulled back into shop and set it up for next morning to go back up on lift for further inspection.

Between my instructor who insisted I needed a new radiator, and my dad who insisted that I had a clogged hose - this after I reminded both that not everything had been checked - I finally convinced my instructor to walk me through the process of pulling the water pump out to inspect it. Once up on lift, determined NOT to be 8 hours or more getting through the process, I pulled the right front tire off and removed a section of the black plastic wheel well protector and removed the water pump.

After several busted knuckles and multiple swear words, it finally came out. Once fan was exposed, it was rusted and ruined (looking more like coolant rust rather than the normal "rust" one would expect) and not even 20,000 good miles on the pump which should have gotten at least 50,000 miles I replaced it again and added more fresh coolant to system. After 4-1/2 hours, much frustration from being told that I was wrong, I can't begin to explain how good I felt doing it myself and making liars out of my dad and my instructor.

Goes to show you ALWAYS check all obvious items first, then proceed to other less likely Parts until you find the problem. Because I honestly can't imagine spending $200 and not fixing my problem, and still having to spend another $100 to correct things.

2007 Pontiac G6 3.5L engine, had no clue initially that water pump was the problem. Car lost power and speed, I/P lit up like a Christmas tree, pulled over and checked under hood, found serpentine belt off pulley and couldn't get it back on. Finally late afternoon after work, finally figured out problem was water pump because temp gauge kept climbing on the way home. Guy who diagnosed problem was impressed with the fact I had figured out problem (which at the time I couldn't fix), he went through the top moving hoses and whatever else needed to move, or be removed to fix problem. Took 8-1/2 hours to fix/replace water pump. My understanding is they're supposed to last at least 50,000 miles so I figured I was okay for a long while. Amazingly the thermostat itself was in reasonably good shape, so left in place.