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bad thermostat?

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crazyquik22023

10+ Year Contributor
641
6
Sep 14, 2008
Akron, Ohio
My car is overheating and i'm not sure why. I have a newer thermostat, newer radiator, brand new coolant lines everywhere, new OFH gasket and oil cooler o ring just replaced. My car overheats everytime i drive it but it tries to cool down(CEL flashes on and off for a while then just stays on). DSMLink temps are at around 226-230 degrees. After i shut my car off it sucks up all of the coolant from the resevior... so would this be a bad thermostat??? i'm out of ideas otherwise any info would help thanks..
 
It sounds like a head gasket. What happens when you top off the coolant? How long ago did you do the cooling system work? Maybe a big air bubble that needs to be burped out. Make sure your cooling fan is coming on too. Do you have any noise coming from the watert pump? Is it new? Pull a spark plug and see if there is coolant on it. Do you have a cooling system pressure tester? Hook it up and start the car, See how fast the pressure builds, That is one way to see if it is a head gasket. It could be a bad radiator cap letting coolant out and air in. If all checks out you can try a 180 degree t stat, Your front mount may be blocking flow from the radiator. I did the 180 in my car as soon as it got hot out, It helped alot! Also,
Does the car miss at all. The only time i have seen a check engine light flash is from a missfire. Pull the code and see whats up.
P.S. Akron Ohio is cool. Alot of good music came from there in the 80's, DEVO!!
 
it's not the headgasket, the radiator cap is brand new, coolant does flow through the thermostat when the car is idling so this means that its not the water pump correct?? it overflows out of the radiator cap a little but then starts to flow normally and it sucks up coolant while idling but when i drive it starts to overheat... also i have about a 2 month old failsafe 180 deg thermostat
 
WP sounds like it tooka big crap in the crapper-not moving fluid too well..or got the T-stat in upside down...spring needs to go towards the block.

Also, you could have an air lock problem and to cure this is to take the t-stat out and drill a .050 hole in the flange (if there is no wiggle valve on the flange..) to burp the system.

420A's with the T-stat being mounted horizontally, really need to do this trick (and put the drilled hole TDC when putting the T-stat back in..) for these really can have this airlock problem... it's a Chrysler thing.

-DSM
 
"it overflows out of the radiator cap a little but then starts to flow normally"

Is the cap on when this happens? I would start with a new cap. It is cheap and easy. See if that helps. I have seen this happen before.

Burping the system is very important too. You have to get all the air out or else it will push coolant out the cap and overflow. A spill proof funnel is key.
I wouldnt jump to conclusions with the water pump just yet. Check the basics first.
 
"it overflows out of the radiator cap a little but then starts to flow normally"

Is the cap on when this happens? I would start with a new cap. It is cheap and easy. See if that helps. I have seen this happen before.

Burping the system is very important too. You have to get all the air out or else it will push coolant out the cap and overflow. A spill proof funnel is key.
I wouldnt jump to conclusions with the water pump just yet. Check the basics first.

this happens with the radiator cap off, and the radiator cap is brand new like 5 days old so that is not it, and i also "burped" the system i let the car idle for about 30 min with the radiator cap off which should get all of the air bubbles out of the system and i squeezed the lower radiator hose and the covered the thermostat hole to also burp the system....
 
I am having the same issue. Car over heats. While it cools down, it sucks all the coolant from the reservoir. I'm giong to check my spark plugs this weekend to see if its my head gasket. I've changed the radiator cap, burped the system with a funnel, new 180 thermostat, coolant passes through thermostat housing quickly when thermostat opens. I'm also out of ideas.
 
...I'm just wonderin' if you fellows just might have a radiator issue if you've done all the other stuff..(short of not thinking of a cracked HG)

...has any of you guys physically taken the radiator out of the car, shoot a garden hose with a high pressure nozzle on the end, in both ends of the radiator and pressure flushed the thing out, then take that same hose and shove it in both the coolant opening and the lower radiator hose with the T-stat out to flush out the block and heater core?

Why I say this for I've had overheating experiences myself with similar attempts posted above and this is what I finally had to do and my results (and my radiator was so full of rust and junk that it was sickening and the block had so much rust along with the heater core full of gunk as well) was that my overheating conditions were eliminated with this procedure with my tricks above.

..something to ask and then to share .. Good luck-DSM
 
Hello all, I am new to these forums. I have a 95 NT Eclipse RS. For the first time this evening I noticed a small puddle of coolant coming from my car while I was opening the garage door to park. I popped the hood to find that my overflow was well..overflowing onto the ground from its escape hose. I shut the car off and popped the cap off the overflow to see if it was oily at all..negative..the strange thing is that the coolant was only warm..I felt it with my finger. I then went inside to let the car cool down. I went back outside, opened the radiator cap and then proceeded to look into the overflow again..coolant was still up past the hot mark at this time. I checked my oil and oil cap for any strange residue since I know my car has a leaky head gasket. I checked the exhaust for any white smoke, or coolant smell..nothing. No residue and my oil was clean without any coolant odor to it at all. I then proceeded to start the car and let it run with the cap off...slowly as the car warmed up I could see the thermostat open up and start spewing coolant.
What could be the problem? I have a guy that is due to fix my leaky head gasket this week.
 
I noticed a small puddle of coolant coming from my car while I was opening the garage door to park.
Usually what happens is that you got small hoses coming from the main return line of the water pump to the intake manifold and these hoses love to get tired and brittle .. and begin to leak. And welcome and good luck - DSM
 
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