Has anyone had any issues with overheating where the cooling system is full, with a low temp thermo, and the car still overheats in sity driving? I'm starting to think that I've got a bad water pump, but I wanted to be sure before I spent the money for it.

 

Does the pump leak, or make grinding noises? If not, does the fan kick on? And lastly, what temp are you hitting?

BTW, A cooler than stock theromostat alone will not lower your operational temps.

 

is the air damn under the car intact?

 

Thermostat fits backwards, but it dont work that way. Make sure its in right.
Then move to pump. Is the rad hose get hard like it's building pressure?
Also you can do a system pressure test to see if the pump is leaking out the weap hole. If no and pressure leaks you might have a head or head gasket problem.

When hot does your heater blow hot or cold?

 

Yes I have had leaking for a while now, but from what I can see it appears to be at the lower hose joint, so I have chalking it up to a bad hose, or connection.
I have the fan on at all times since the previous owner butchered the wiring under the hood.
I have been hitting 260 again as if my fan wasn't working, which I did double check.
No, a 165 thermo does not mean that it will make the engine run cooler, just that the thermo will open sooner(ie @ 165F)

 

No, had to be removed earlier due to some damage, but car was still running cooler after removing that then it is now.

 

Yes it was in correct, I replaced it a couple month ago to be sure that wasn't the problem and made sure to read the thermo when installing it.
Hoses didn't build pressure, that would 'mean' a clogged radiator if it were the upper one. Haven't done a pressure test on it, don't have the equipment to do that. And yes, when I use the heater, unless the coolant has been scorched out it will blow hot air. In fact the only passage through the radiator has been from the heater core.

While I was at work I took the thermo out to see how flow was through the radiator and how hot it would get without it in. Now when I went to work I was still having problems keeping the engine cool, especially during stop and go traffic on-post, once again topping out at 260(the very top of the red area). But when I pulled it out and turned the car on, I immediately noticed that there was actually flow through the top of the radiator. I have not seen that the entire time that I've owned the car, since sept 08. When I bought it I made mention of the pump leaking, and was told that he would fix it. Since then I don't think he did since the pump still looked old(he used the excuse that he had one sitting around), and it still leaked. On my drive home, about 45 min, the temp guage never made up to halfway between the first two marks. And the heat coming from the vent was warm but not hot, and the temp outside was only down to 57F. I have had some serious concerns about my head gaskets too with the "lack" of power that I was expecting, but now I'm thinking its more from a bad water pump.

 

You mention leaking. From where? The weap hole on the pump or the overfill/overpressure vent?

If its at the weap hole, change the water pump asap. Leak at the weap hole is your final notice. Don't drive on it cause next the pump will really start leaking. And ask anybody, it will happen at the worst possible time for you. And when it really leaks I mean you will shut off your motor and the pump will be blowing steam & hot fluid out.

 

Like I said I can't really tell where it's leaking from, but I broke down and bought one today from Advance. Hopefully when I install it on saturday it'll end my issues. If it doesn't, or only minimizes them, then I will know for sure that I have a head gasket issue that I've been trying to avoid. Yes, seems like I have better power when the coolant fluid level is low. I would rather replace something cheap and easy to get to rather than something complicated and time consuming.

 

If it is bad you should see a stain below the weap hole.

 

If your cooling fans are running all the time..you shouldn't have a problem. You might have a cloged radiator, or somewhere in the cooling system....maybe take the radiator out and have it "roded" (cleaned) at a radiator shop....you also might have a bad head gasket or something to that effect....also, is your temp gauge working correctly?? But for sure try the water pump first. I removed my thermostat completly and put in a restrictor plate in mine.....you get them at a performance store...or like summit...but don't run with no thermostat/restrictor plate...also you can make your own restrictor plate by taking the center out of the thermostat itself.