Help: Overheating WITHOUT a thermostat
02-12-05, 12:00 PM
#1
Help: Overheating WITHOUT a thermostat
As the weather generally gets warmer, so does my temp. I "cored" a thermostat I picked up at Autozone yesterday as a temporary fix until I got the time to get a Mazda one. But, the car still runs too warm. I did the coolant seal test a few mins ago, (take EGI fuse out, take filler cap off, crank) but no coolant came out. I'm thinking maybe a clogged radiator or heater core. Any help or past experiences with this problem would be great.
Edit: I bought all belts, changing them tomorrow
Edit: I bought all belts, changing them tomorrow
Last edited by White87FC; 02-12-05 at 12:03 PM.
02-12-05, 12:13 PM
#2
Rotor Head
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When the engine is very warm.. Check for cold spots on the radiator, signifying a clog.
Or you could drop all the coolant... And do a full flush, see what happens
Or you could drop all the coolant... And do a full flush, see what happens
02-12-05, 12:18 PM
#3
Haven't we ALL heard this
Read up on this ....
http://www.mazdamotorsports.com/weba...ubject=cooling
Also, do you have your underpan still installed?
BEfore you freak out on temps...you really need to get an aftermarket water temp gauge to see what is REALLY going on.
James
http://www.mazdamotorsports.com/weba...ubject=cooling
Also, do you have your underpan still installed?
BEfore you freak out on temps...you really need to get an aftermarket water temp gauge to see what is REALLY going on.
James
02-12-05, 12:43 PM
#5
Originally Posted by White87FC
As the weather generally gets warmer, so does my temp. I "cored" a thermostat I picked up at Autozone yesterday as a temporary fix until I got the time to get a Mazda one. But, the car still runs too warm. I did the coolant seal test a few mins ago, (take EGI fuse out, take filler cap off, crank) but no coolant came out. I'm thinking maybe a clogged radiator or heater core. Any help or past experiences with this problem would be great.
Edit: I bought all belts, changing them tomorrow
Edit: I bought all belts, changing them tomorrow
1 - My first experience, the car would loose coolant while the engine was running, it never really overheated. Turns out the housings were corroded!
2 - The second expierience, the car was loosing coolan, turns out it was the radiator cap.
3 - The third one, overheating while crusing, turns out it was cloged radiator; i also replaced teh water pump because it had a small leak.
4 - The fourth one, jut like yours, turns out that the efan was connected as a pusher instead of puller.
02-12-05, 04:11 PM
#6
Engine, Not Motor
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Originally Posted by White87FC
As the weather generally gets warmer, so does my temp. I "cored" a thermostat I picked up at Autozone yesterday as a temporary fix until I got the time to get a Mazda one. But, the car still runs too warm.
Start by installing a proper Mazda thermostat. Then, check out http://www.aaroncake.net/rx-7/cooling.htm for cooling system troubleshooting.
02-12-05, 04:42 PM
#7
Originally Posted by Aaron Cake
Not surprising. The Mazda thermostat is a bypass type. If you run without one, or a cored thermostat, the bypass hole in the bottom of the thermostat neck will not be closed. This will cause the majority of coolant to totally bypass the rad.
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02-12-05, 06:03 PM
#8
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Aaron is right. If you don't have one the water will just flow back into the engine without going through the rad. Get a Genuine MAZDA thermostat. If your still having heat issues it's a dirty rad or your fan is not working like it should. Electric fan or clutch type? And yeah you wanna keep the underpan on to keep air flowing through and not around the radiator.
02-12-05, 06:11 PM
#9
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Originally Posted by Aaron Cake
Not surprising. The Mazda thermostat is a bypass type. If you run without one, or a cored thermostat, the bypass hole in the bottom of the thermostat neck will not be closed. This will cause the majority of coolant to totally bypass the rad.
Start by installing a proper Mazda thermostat. Then, check out http://www.aaroncake.net/rx-7/cooling.htm for cooling system troubleshooting.
Start by installing a proper Mazda thermostat. Then, check out http://www.aaroncake.net/rx-7/cooling.htm for cooling system troubleshooting.
02-12-05, 10:54 PM
#10
OK, thanks for the input. I've replaced the rad. cap. I've still got the stock clutch fan that is still good(doesnt spin freely when you spin it). And the cored t-stat, as I said, is a temporary fix until the mechanics at the dealership get back to work on Monday so I can order one.
02-12-05, 11:07 PM
#11
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Originally Posted by KNONFS
I have different issues with overheating\loosing coolant!
1 - My first experience, the car would loose coolant while the engine was running, it never really overheated. Turns out the housings were corroded!
2 - The second expierience, the car was loosing coolan, turns out it was the radiator cap.
3 - The third one, overheating while crusing, turns out it was cloged radiator; i also replaced teh water pump because it had a small leak.
4 - The fourth one, jut like yours, turns out that the efan was connected as a pusher instead of puller.
1 - My first experience, the car would loose coolant while the engine was running, it never really overheated. Turns out the housings were corroded!
2 - The second expierience, the car was loosing coolan, turns out it was the radiator cap.
3 - The third one, overheating while crusing, turns out it was cloged radiator; i also replaced teh water pump because it had a small leak.
4 - The fourth one, jut like yours, turns out that the efan was connected as a pusher instead of puller.
02-13-05, 03:02 AM
#12
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Originally Posted by Aaron Cake
Not surprising. The Mazda thermostat is a bypass type. If you run without one, or a cored thermostat, the bypass hole in the bottom of the thermostat neck will not be closed. This will cause the majority of coolant to totally bypass the rad.
Start by installing a proper Mazda thermostat. Then, check out http://www.aaroncake.net/rx-7/cooling.htm for cooling system troubleshooting.
Start by installing a proper Mazda thermostat. Then, check out http://www.aaroncake.net/rx-7/cooling.htm for cooling system troubleshooting.
02-13-05, 03:14 AM
#13
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02-13-05, 08:10 AM
#14
Originally Posted by West TX RX-7
Aaron is right. If you don't have one the water will just flow back into the engine without going through the rad. Get a Genuine MAZDA thermostat. If your still having heat issues it's a dirty rad or your fan is not working like it should. Electric fan or clutch type? And yeah you wanna keep the underpan on to keep air flowing through and not around the radiator.
Last edited by KNONFS; 02-13-05 at 08:20 AM.
02-13-05, 08:11 AM
#15
Originally Posted by mycarisolderthanme
i cant believe that. i was running much too hot at one point so i pulled the tstat. the car never got above 1/8 on the temp guage.. ran much cooler than before i yanked it. this is on an s4 se.. maybe the tstats are different for years and models?
02-13-05, 08:14 AM
#16
Originally Posted by 88turbotime
Woah, dude! please elaborate on #1 for me. My car has been losing coolant like a **** recently, it has to be while driving because there is not as much as a spot under the car no matter how long it sits. It doesnt overheat either. I dont know where it is going!
On my first issue, I could literally see water coming out of the overflow tank
02-13-05, 10:01 AM
#17
Engine, Not Motor
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Originally Posted by White87FC
OK, thanks for the input. I've replaced the rad. cap. I've still got the stock clutch fan that is still good(doesnt spin freely when you spin it). And the cored t-stat, as I said, is a temporary fix until the mechanics at the dealership get back to work on Monday so I can order one.
02-13-05, 11:54 AM
#18
Originally Posted by Aaron Cake
Even an afermarket thermostat will be better then the cored unit.
Again, have you run a FC without Tstat during the summer?
I understand were you are coming from, and it is true for road racing applications. At the end, yes I would run a OEM Tstat, but just saying that not running one will cause the car to overheat, is just not true.
02-14-05, 10:12 AM
#20
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Originally Posted by KNONFS
How is that?
Again, have you run a FC without Tstat during the summer?
Again, have you run a FC without Tstat during the summer?
Really, there is NO REASON to remove the thermostat unless it's a track car.
02-14-05, 02:12 PM
#21
Originally Posted by Aaron Cake
Not me, since I understand how the cooling system works and don't hack it. But I have dealt with two seperate cars that were overheating constantly, traced to the removal of the thermostat without blocking off the bypass port.
Really, there is NO REASON to remove the thermostat unless it's a track car.
Really, there is NO REASON to remove the thermostat unless it's a track car.
I am not arguing the fact that it is better to use a tstat for the street, but don't agree with the overheating issue due to no tstat; and I have experience on that one.
02-14-05, 02:34 PM
#22
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For some people, it seems to work. Probably has a lot to do with the weather, their coolant/water mix, the state of the rest of the system, e-fan or clutch fan, etc.
But I still don't know why people would remove the thermostat. It doesn't improve cooling, and has only negative effects.
If you have a track car and actually have a reason to remove the thermostat, then go ahead. Just remember to block that bypass hole in the water pump housing.
But I still don't know why people would remove the thermostat. It doesn't improve cooling, and has only negative effects.
If you have a track car and actually have a reason to remove the thermostat, then go ahead. Just remember to block that bypass hole in the water pump housing.
02-14-05, 03:49 PM
#23
You have to be careful when you say 'the car never ran hot without the thermostat'. What you are saying is that the coolant temperature never read more than a certain temperature. Other than bypassing the radiator, the thermostat is there to slow the flow of coolant throughout the engine. If the coolant is travelling too quickly throughout the motor, it cannot properly and efficiently absorb heat. In essence, the transfer of heat from the engine to the coolant cannot happen well enough.
So, while the coolant temperature (and that on the guage) may seem ok, the engine is cooking. What may read 1/4 on the guage may actually be 3/4. You need the thermostat in there to regulate the flow rate (and therefor heat transfer rate) of the coolant as well as the flow path.
So, while the coolant temperature (and that on the guage) may seem ok, the engine is cooking. What may read 1/4 on the guage may actually be 3/4. You need the thermostat in there to regulate the flow rate (and therefor heat transfer rate) of the coolant as well as the flow path.
02-14-05, 04:36 PM
#24
Originally Posted by Aaron Cake
For some people, it seems to work. Probably has a lot to do with the weather, their coolant/water mix, the state of the rest of the system, e-fan or clutch fan, etc.
But I still don't know why people would remove the thermostat. It doesn't improve cooling, and has only negative effects.
If you have a track car and actually have a reason to remove the thermostat, then go ahead. Just remember to block that bypass hole in the water pump housing.
But I still don't know why people would remove the thermostat. It doesn't improve cooling, and has only negative effects.
If you have a track car and actually have a reason to remove the thermostat, then go ahead. Just remember to block that bypass hole in the water pump housing.
The first tiem I ran the car without a tsta, was because it stopped working, so I did as a temporary fix. Turns out that the temporary part wasn't so temporary...
02-14-05, 04:46 PM
#25
Originally Posted by Nick86
You have to be careful when you say 'the car never ran hot without the thermostat'. What you are saying is that the coolant temperature never read more than a certain temperature. Other than bypassing the radiator, the thermostat is there to slow the flow of coolant throughout the engine. If the coolant is travelling too quickly throughout the motor, it cannot properly and efficiently absorb heat. In essence, the transfer of heat from the engine to the coolant cannot happen well enough.
So, while the coolant temperature (and that on the guage) may seem ok, the engine is cooking. What may read 1/4 on the guage may actually be 3/4. You need the thermostat in there to regulate the flow rate (and therefor heat transfer rate) of the coolant as well as the flow path.
So, while the coolant temperature (and that on the guage) may seem ok, the engine is cooking. What may read 1/4 on the guage may actually be 3/4. You need the thermostat in there to regulate the flow rate (and therefor heat transfer rate) of the coolant as well as the flow path.
Actually the second time I ran the car without a Tstat was when I was having some overheating issues on my newly na to T2 conversion. The stock sensor was on the stock location, and the aftermarket sensor was next to the tstat location. After fixing the overheating issue, both gauges, plus the E6K sensor showed the same readings (at least the aftermarket temp sensor and E6k, can't really tell the exact temp on the stock gauge), and there was no sign of overheating at all. This time, I ended up putting the tstat back when winter arrived.
Last edited by KNONFS; 02-14-05 at 04:51 PM.