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420A Overheating and Need major advice

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charlie506

Probationary Member
7
0
Aug 20, 2016
Benton Harbor, Michigan
Hey guys,
I have a 1997 Eclipse non turbo (420a). My car has started to over heat and I have done so much to try and stop the problem, but no luck. Even mechanics in my area are stumbled upon what the problem could be. I have replaced radiator hoses, and radiator, the radiator cap and has had a coolant flush done to it. I have tried to burp the air out of the system, but it appears to be getting some major air bubbles somewhere. I have had pressure check done to it and it passed it. I have also had a combustion leak down test done to it and it passed. Their is no oil in the coolant or coolant in the oil. Does anyone know what this might be. Please help me my fellow friends.
 
Overheating as in, temp gauge leaning towards red and shut car down and pop the hood and coolant overflow is bubbling?

Who pressured tested the coolant system? And was the thermostat replaced?
 
I just replaced the thermostat yesterday and I had Midas auto repair shop do a pressure test on the system 4 times and it passed every time. So I just confused on what the problem could be.
 
maybe a bad water pump

is the radiator fan kicking on?
 
Yes the radiator cooling fan is coming on, but my a/c fan does not come on. That shouldn't affect the cooling of the car if i don't have the a/c on though. I have replaced everything in the cooling system but the water pump because when the radiator cap is off I can see the water flowing and I don't see any visual leaks of it.
 
any time the A/C switch is on in the car, both fans should turn on, even if the engine hasn't warmed up.

here is some info if you wanna make sure that both fans are working in both HI and LO.

also you might wanna check the coolant temp sensor. i have had one giving an incorrect reading to the ECU. The fan would kick on but only after it was overheating. It ended up the ecu was seeing a temp about 25 degrees lower than it actually was.

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Ok ill do some test on it tomorrow and through out the week. I thought the cooling fan Hi and Low relay was good because you can hear the fan switch from slow speed to a very high speed. Of course I need to check the relays for the a/c fan tomorrow though. I will also take a look at my coolant temperature sensor. Any other suggestions. I thought their was maybe just a lot of air in the coolant system so I burped it. I noticed when I burp the system the coolant will violently spill and bubble out of the radiator once the car gets operating temperature. I don't know why it's doing that.
 
I had the same thing on my jeep after I replaced the water pump. I flushed the rad several times, and pressure tested good. Turns out there was sediment clogging the rad only after running for awhile, and with the cap off a geiser would shoot out every 15 mins or so, with a bunch of crud mixed in.
I replaced the 2 year old 1 row rad with an aluminum 3 row and fixed it.
You can get an OEM style rad for $50 all day, or upgrade to all aluminum for under $100. EBay rads have always worked for me.
 
Well I bubbles like crazy constantly once the car is warmed up. I don't suspect anything clogged because I did a system flush on it 3 times and the radiator is brand new. Only a couple months old.
 
Hey guys,
I have a 1997 Eclipse non turbo (420a). My car has started to over heat and I have done so much to try and stop the problem, but no luck. Even mechanics in my area are stumbled upon what the problem could be. I have replaced radiator hoses, and radiator, the radiator cap and has had a coolant flush done to it. I have tried to burp the air out of the system, but it appears to be getting some major air bubbles somewhere. I have had pressure check done to it and it passed it. I have also had a combustion leak down test done to it and it passed. Their is no oil in the coolant or coolant in the oil. Does anyone know what this might be. Please help me my fellow friends.[/QUOTE
Hey guys,
I have a 1997 Eclipse non turbo (420a). My car has started to over heat and I have done so much to try and stop the problem, but no luck. Even mechanics in my area are stumbled upon what the problem could be. I have replaced radiator hoses, and radiator, the radiator cap and has had a coolant flush done to it. I have tried to burp the air out of the system, but it appears to be getting some major air bubbles somewhere. I have had pressure check done to it and it passed it. I have also had a combustion leak down test done to it and it passed. Their is no oil in the coolant or coolant in the oil. Does anyone know what this might be. Please help me my fellow friends.
First I'd Check for any leaks then check water pump to make sure bearings are good and that it actually is pumping your coolant. Also check thermostat to make sure it opens at the right temperatures. If you know for a fact both are working properly then look at your radiator and make sure your coolant is flowing inside like it needs to be. If dirt or anything like that is in the radiator It could plug the holes inside causing inefficient flow and over heating. Make sure radiator fan kicks on when thermostat opens if not that is a issue. As stupid as it sounds make sure your coolant isn't being stopped by a plugged line from reservoir to thermostat. Lastly if all these things work I'd check with a real thermometer (one capable of at least 250 degrees) to see how hot you get and to confirm your temperature sending unit and or temperature gauge isn't faulty. You can rent a Digital thermometer from auto parts store I believe. If you do that strap it to the radiator hose going in the radiator turn the car on and watch. I don't recommend you let the motor get any hotter then 230 degrees.
 
Well I bubbles like crazy constantly once the car is warmed up. I don't suspect anything clogged because I did a system flush on it 3 times and the radiator is brand new. Only a couple months old.

bubbling constantly in the overflow when warm and overheating sounds more than likely the HG. I replaced a HG on 420A (97 eclipse rs) On long (25 min) drives the car overheated and violently bubbled out of the overflow. Once the gasket was replaced his car was fine. No overheating, no bubbling overflow, no burning coolant/water mixture.
 
Yes I agree. If you have already replaced the water pump and the thermostat And still get air bubbles. Then the head gasket would be next to replace. Chances are that is the issue with the over heating.
 
Ok i will perform all these test to see if any of these could be the problem, but if the water pump bearings are bad wouldn't their be a visual leak? Also we did a combustion leak test multiple times and it showed absolutely no signs of a bad head gasket.
 
Well if you are lead to believe your water pump has an issue There are two ways to test your water pump to see if it's bad one way is to loosen the tension of the belt then grab the water pump pulley and try to rock it up and down there's any slack the new bearings are shot and the pump is bad and the other way to tell is if you're leaking coolant from the pumps gasket itself. so if you say you see No noticeable leak then I'd check to see if the bearings are bad. Of course this involves getting all the way down to the crank - pulling timing belt etc witch if you don't know how to put it back can easily damage or further damage your car. So with that being said I would absolutely 100% check everything else before doing it. And if you already done that sort of job before you'd know that its not the funniest of all jobs
 
My 420a was doing the same thing even after a new head gasket, water pump, the whole works... It happened to be a defective Rad cap that I had bought brand new. I only found out because I used another cap with built in thermometer,temporarily. Try that,if not then it's the HG. My Teggy is doing the same boiling in reservoir deal. N it's the HG cuz it consumes a gal of water in 3days.
 
Now that I think of it it wouldn't be that bad considering all you have to do is release tension to your timing belt to get down to the pump and when you it back together all you have to do is timing. And in fact I think the hardest part about it all would be to get to get That stupid plastic cover for the belt itself off oh and the motor Mount has to be Pulled
 
If your head gasket had a leak you would experience loss of compression causing rough idol, you would also feel a loss of power when accelerating and your car would run like crap , if it even ran. Either you have compression or not. for a head gasket to leak like that and the motor still function it would have to be really small and you would more than likely have a oil leak. Anyways for that matter you would have low head pressure due to the leak and head temperature wouldn't be as hot unless oil levels are low in witch case you could overheat. Honestly I don't see how a bad HG would effect anything other then compression loss. Temperature shouldn't even be effected unless your oil levels were low.
 
So I have done all test again and still no signs of a bad head gasket. Does anyone have any clue why when I burp the cooling system, when the thermostat opens up. The coolant will start puking out of the radiator like crazy. It's like I have really a lot of air trapped in the engine. My coolant level does not just rise and drop when burping the system like a normal car. Any more suggestions?
 
I had a headgasket leaking between the cylinders just enough to loose coolant, but never had one solid sign it was bad.. No mixture in the radiator/motor leak down test was fine ect..leave the cap off let the car sit at idle with the cap off, and coolant as needed to see if it stops burping.
 
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