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Help Please! overheating and coolant overflow

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Old Apr 14, 2011 | 01:20 PM
  #1  
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Default Help Please! overheating and coolant overflow

Driving home last night my car started to overheat hanging around 230 while I was on the highway. I was almost home when the temp gauge quickly climbed to 260 and the check gauges light came on. I pulled off the road as quick as I could but before I did the engine lost a lot of power, started stuttering, and the car started to vibrate. I'm hoping that it just went into a limp home mode. I Let it cooldown and then drove it the rest if the way home and it seemed to run fine but was still overheating.When I popped open the hood to take a look I checkedall the hoses and radiator and nothing was leaking and everything was hot to the touch, I'm guessing the coolant circulation was fine. the fans were on as well and even stayed on after I turned the car off. Opened up ther over flow and it was full to the brim and had obviously been spilling coolant out. also sounded like the coolant was boiling inside of the hoses with the engine turned off. planing on replacing the t-stat today along with the cap, these were the only solutions I could find by searching the other threads. Any more ideas on what it could be? Thanks
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Old Apr 14, 2011 | 08:49 PM
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It could be many things.

Did you replace the tstat and cap yet?

If your coolant hasn't been flushed recently especially if it's still dexcool, do that.

Maybe the headgasket is starting to go? Compression test.

Maybe radiator is clogged? Check if whole thing is hot at full temp.

Heater core clogged? Check heat.

Water pump failure? Any leaks by the pump?
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Old Apr 15, 2011 | 07:10 PM
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sounds like its either a leak or tstat to me. check for leaks if its ok check your tstat.
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Old Apr 15, 2011 | 09:22 PM
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Willing to bet its a stuck thermostat. No leaks... It's either stuck or something is clogged. Just go to the zone and get a new TStat. I'll bet that's it.
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Old Apr 18, 2011 | 02:51 PM
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UPDATE... Sure as hell is hot it was the t-stat, guessing it got stuck closed and finally gave way when the motor overheated. Replaced the bad t-stat with a 160* one from autozone (I think it was a motorad brand, made in germany). Flushed the system a few times with tap water then filled it up and bled the air out of the system. For the passed few days it has just had the plain tap water in it and i plan on draining that then running a chemical flush through it. After that I'll use a peak flush kit (the one that hooks up to the garden hose) to clean it all out. I am also getting away from Death-Cool and just going to run a 50/50 mix of the new prestone universal coolant and distilled water. Any objections to any of this?
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Old Apr 18, 2011 | 03:07 PM
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Here are some pics for those wondering...
First is what poured out of the overflow before cleaning, Second is what came out when i drained the cooling system (Wrench for reference of cloudiness). third is what came out of the overflow after a few rinses with the garden hose.
Attached Thumbnails Help Please! overheating and coolant overflow-img_20110414_154148.jpg   Help Please! overheating and coolant overflow-img_20110414_154200.jpg   Help Please! overheating and coolant overflow-img_20110414_154738.jpg  
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Old Apr 18, 2011 | 03:08 PM
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I've used DexCool in hundreds of cars with no issues and I don't see the need for changing it over. My personal car cruises around in the 100 degree Florida heat with no air dam and doesn't get over 200. However, DexCool is free to me so that's probably why I stick with it.
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Old Apr 18, 2011 | 07:05 PM
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there is nothing wrong with dexcool. it didnt cause the thermostat to stick closed. your coolant system probably wasent flushed correctly or someone put green or tap water in your system. these dont mix with dex. only dex or distilled water mix with dex.

the coolant in the second picture is perfectly normal for getting overheated and boiling. the **** in the overflow is a mixture of dirt and other moisture accumulating in the overflow bottle being it is not sealed, just capped. when the dexcool mixes from the radiator into the overflow, it turns to sludge. thats a major reason people have so many problems with dex in these cars is because the overflow is not designed very well.
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