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Engine Overheating

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Location
Osage Beach, MO, USA
#22
Overheating is when the coolant boils or runs low or out of the system. When the coolant boils, it loses its ability to remove heat from the engine. Naturally a depletion of coolant has the same effect. Depending on the coolant and the pressure the system is designed to run at, the boiling temperature may be as high as 265 or 275 degrees. At atmospheric pressure, 50/50 coolant boils at 225 degrees. However, most cooling systems run at 15 psi (essentially 2 atmospheres), which yields the 265 degree boiling point.

The "normal" temperature for an engine is a coolant temperature of 190-220 degrees, but it's not really overheated until coolant starts boiling. It would be considered "hot" from 230-250.

When you get an engine into the hot range, it's a signal to ease off on your driving stress so that the engine can cool back down to the normal range to avoid the damage that can come with overheating. Here's a good resource on engine cooling: https://www.aa1car.com/library/overheat.htm
 


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Location
Hawthorne, NJ, USA
#23
Finally pulled the trigger on a mountune radiator today. I know I probably won't receive it until fall but the constant 230+ or even 240+ coolant temps are getting to be too much. I plan to keep this car until it falls apart so I figured investing in cooling isn't a dumb decision.
 


M-Sport fan

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Solebury, Pa.
#24
Finally pulled the trigger on a mountune radiator today. I know I probably won't receive it until fall but the constant 230+ or even 240+ coolant temps are getting to be too much. I plan to keep this car until it falls apart so I figured investing in cooling isn't a dumb decision.
Are you seeing those temps only in Joyzee roadway stop and go 'parking lots', or is it getting that hot even during steady state, or regular city/town driving in these ambient temps we're having currently?
 


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Location
Hawthorne, NJ, USA
#25
Are you seeing those temps only in Joyzee roadway stop and go 'parking lots', or is it getting that hot even during steady state, or regular city/town driving in these ambient temps we're having currently?
I first really noticed it when I was driving up a hilly area with the AC on. The temp skyrocketed to 245 and the engine light came on. I figured it was a one-time thing but I've been getting them even cruising with the AC on. Lately everywhere I go I've been driving with the windows down and the heat blasting and I'm just honestly sick of it. I'm fine at night time when the temperature drops 10 or 15 degrees but during the day fugedaboutit
 


Dpro

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Location
Los Feliz (neighborhood in LA)
#26
So is the general consensus that the Mountune is a better choice than the Mishimoto? After I get my long block installed this will be my next purchase.....should have been my first!
CSF builds the Mountune radiator. Mishimoto builds their own. CFS is built in Indonesia the Mishimoto is built in China.

Mishimoto has been known in the past for quality control issues and fitment issues. Yet there are quite a few people running them. They were the first to the market in the FiST world here in the U.S. Mountune’s came in a little after Mishimoto.

Both radiators will work but in the end I think the overall satisfaction of people who have the Mountune speaks volumes. Both are not cheap either and I believe the Mountune is a bit less. Especially when on sale.
With that said I have the Mountune and trust the Mountune . I know of Mishimoto from the 240sx world were they got their start as knockoffs of Koyo’s. Koyo’s were Japanese made aluminum radiators. They have been in business for 64 years now.
Mishimoto is an American run overseas manufacturer of radiators that started in 2005.

CSF/Mountune- actually started over 70 years ago but did not become CSF officially till 1975 they were American made radiators and they still have a plant here in SoCal for some of their product. They are a family owned business and have been for those 70 years. They have done some innovative stuff in radiators as well. Their product for our car is made in Indonesia but they have pretty damn good quality control.

You make the choice.
 


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Location
Cranbrook, BC, Canada
#27
CSF builds the Mountune radiator. Mishimoto builds their own. CFS is built in Indonesia the Mishimoto is built in China.

Mishimoto has been known in the past for quality control issues and fitment issues. Yet there are quite a few people running them. They were the first to the market in the FiST world here in the U.S. Mountune’s came in a little after Mishimoto.

Both radiators will work but in the end I think the overall satisfaction of people who have the Mountune speaks volumes. Both are not cheap either and I believe the Mountune is a bit less. Especially when on sale.
With that said I have the Mountune and trust the Mountune . I know of Mishimoto from the 240sx world were they got their start as knockoffs of Koyo’s. Koyo’s were Japanese made aluminum radiators. They have been in business for 64 years now.
Mishimoto is an American run overseas manufacturer of radiators that started in 2005.

CSF/Mountune- actually started over 70 years ago but did not become CSF officially till 1975 they were American made radiators and they still have a plant here in SoCal for some of their product. They are a family owned business and have been for those 70 years. They have done some innovative stuff in radiators as well. Their product for our car is made in Indonesia but they have pretty damn good quality control.

You make the choice.
I think you just did that for me....Mountune sounds like the way to go for me. Thanks for the info! Man I just love this Forum!
 


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Location
Hawthorne, NJ, USA
#28
I think you just did that for me....Mountune sounds like the way to go for me. Thanks for the info! Man I just love this Forum!
Just a heads up I ordered mine from mountunes website today since they actually say in stock and got an email saying it already shipped so if you're going to pull the trigger now is the time. $475 includes shipping.
 


jayrod1980

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Viva Las Vegas!
#30
The Mountune radiator also installs like stock. It takes up less room than the Mishimoto and doesn’t require you to move your fan over to their proprietary housing.
 


vmaxbaby

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Location
Winchester, VA, USA
#31
So if I understand if your going to do a stage 2 tune, because of the extra heat you need to upgrade the Radiator? To go along with that question if your tuned and don't get into boost are you still making more heat. My example is the wife drives it a few days a week and I know she doesn't run the car hard at all but I don't want her to have over heat issues because she is going to call me :( Living in Virginia we do have 2 months of 90+ after that 80's and 70's outside till winter. I have a 2019 with no over heating issue at the moment but a tune will be coming after my IC install.
 


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Location
Virginia
#32
So if I understand if your going to do a stage 2 tune, because of the extra heat you need to upgrade the Radiator? To go along with that question if your tuned and don't get into boost are you still making more heat. My example is the wife drives it a few days a week and I know she doesn't run the car hard at all but I don't want her to have over heat issues because she is going to call me :( Living in Virginia we do have 2 months of 90+ after that 80's and 70's outside till winter. I have a 2019 with no over heating issue at the moment but a tune will be coming after my IC install.
When my '15 made a pass at overheating, it wasn't tuned. Just depends a dozen different variables. In that case it was 85 F, I was going 30-40 mph up a 7% grade, and was nearly constantly in boost. Just keep an eye on it, and do it if you want the insurance.
 


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Location
Cranbrook, BC, Canada
#33
I just burned a hole in my #4 piston, probably because of inadequate cooling and I wish my first mod had been a better radiator. Any tune over stock is adding fuel and heat to a cooling system that is barely acceptable for a stock engine. Just my opinion.
 


JDG

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Conshohocken, PA
#34
The first and last photo are of #4 plug, the cylinder with a hole. That little strand is just a piece of lint, it's non-metallic

View attachment 33626 View attachment 33627 View attachment 33628 View attachment 33629 View attachment 33630
Can you post photos of the ground strap head on? Also, probably best to post these in your other thread where most of the discussion has taken place. Very confusing to follow the diagnosis with you posting your info in a bunch of different threads.
 


Messages
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Location
San Diego
#36
I just burned a hole in my #4 piston, probably because of inadequate cooling and I wish my first mod had been a better radiator. Any tune over stock is adding fuel and heat to a cooling system that is barely acceptable for a stock engine. Just my opinion.
My stock ST overheats multiple times every summer. Overheated very badly today driving home through the mountains. The car limped 30-60 MPH at various times...whatever it would allow me do. The check engine light finally came on today for the first time, and I smelt something weird burning. Coolant was topped off and boiling.

I bought my ST new 2 years ago and 2 different dealers can't fix it. One of the dealers wanted to replace the radiator with another stock radiator for $1300. The car is just prone to overheating.
 


M-Sport fan

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#37
^^^$1300.00!!! You could buy the Mountune and then pay someone to install it and still have $400.00 left over from that price!! [crazyeye]
 


Dpro

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Los Feliz (neighborhood in LA)
#38
^^^$1300.00!!! You could buy the Mountune and then pay someone to install it and still have $400.00 left over from that price!! [crazyeye]
At least. lol or he could put the Mountune in himself and pocket $850 lol

I made a point of getting a Mountune radiator living here in SoCal. It meant one less thing I have to think about.
 


Messages
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10
Location
San Diego
#39
At least. lol or he could put the Mountune in himself and pocket $850 lol

I made a point of getting a Mountune radiator living here in SoCal. It meant one less thing I have to think about.
Is the Mountune radiator actually functional at reducing temps, or is just mod bling. I'm moving to Arizona next week, and I don't care about aftermarket bling. I need to fix this overheating issue or replace the car. I love my little ST, but this overheating issue is inexcusable.
 


Messages
253
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258
Location
Virginia
#40
Is the Mountune radiator actually functional at reducing temps, or is just mod bling. I'm moving to Arizona next week, and I don't care about aftermarket bling. I need to fix this overheating issue or replace the car. I love my little ST, but this overheating issue is inexcusable.
Radiators and intercoolers are never bling on this car. The OEM intercooler is just flat out bad, and the OEM radiator is the exact same part they use on the other Fiestas that make 120 hp.
 


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