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Summer coolant temps western states

redmoe

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#1
Hey all

This is my first summer with the FiST and the coolant temp gets pretty high already this summer. Today the ambient temp was about 100 F (AZ) and my coolant temp was around 220 F cruising, 225 to 230 in light stop light traffic and hit 240 F while stuck in line at my kids school for 10 min. This is all with the AC set to 69 F.

I have read that these cars get hot but I wanted to see how other folks cars are running in the hot western states?

Thanks
 


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redmoe

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Thread Starter #3
I just picked up a coolant gauge and it appears that fro. The factory the mix was more like 60 antifreeze 40 water. The manual says you can go 40 antifreeze 60 water. So I am going to slowly shift the ratio and see if that helps.
 


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redmoe

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Thread Starter #4
I diluted the coolant to 40 antifreeze and 60 water last night. So flat the car appears to run at least 10 deg cooler. I drove the car in traffic got the oil temp up to 200 and then let it sit in my driveway for 15 min with the ac on full. The coolant temp topped out at 226. Yesterday in the same conditions (may have been 3 deg warmer outside) I hit nearly 240 after a 10 min idle with the ac in the low 70s. Time will tell but this may buy a little more time on the stock radiator.
 


kivnul

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#5
Those are high temps indeed. I do not monitor mine all the time, but when I do datalogs on pulls (ac off) 70deg outside I just break 200deg coolant temp.
 


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redmoe

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Thread Starter #6
That’s about where my temp are at in those conditions. Cruising at 45 to 50 with the ac on full in 95 deg weather I was sitting around 205 to 207 with the 40/60 mix.
 


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Mesa
#7
The highest I've seen this year so far is 202 on a short on ramp rip.

Last year when I first got my AP and started monitoring temps the highest coolant temp I saw was about 220-ish in traffic, cruising for the most part it'll stay under 200.
 


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redmoe

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Thread Starter #8
The highest I've seen this year so far is 202 on a short on ramp rip.

Last year when I first got my AP and started monitoring temps the highest coolant temp I saw was about 220-ish in traffic, cruising for the most part it'll stay under 200.
Is that with the ac on?
 


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Dublin, OH
#10
I am routinely over 210° and I live in Ohio. I have reached that temperature when it was less than 70° out. in fact, I have seen 215° in very cool weather with my 2017.
 


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redmoe

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Thread Starter #11
Mines a 2017. It’s getting stuck stationary for 5 plus minutes that drives up my coolant temp. Then if I start hitting more traffic there isn’t enough time to get air flowing through the radiator.

Is 202 you peak or is that your average? How long are your drive durations? Sorry for all the questions the reason I ask about the duration is if I drive for about 30 or under my temps are like yours. If I drive longer or only let the car rest for an hour the temps get higher. Just trying to figure out if I need to go ahead and get an upgraded radiator.
 


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redmoe

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Thread Starter #12
I just gave in an bought a Mountune radiator. I am hoping I can install it from the bottom as it looks easier than pulling the front of the car off. I believe Mountune installs from the bottom.
 


green_henry

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#13
I just gave in an bought a Mountune radiator. I am hoping I can install it from the bottom as it looks easier than pulling the front of the car off. I believe Mountune installs from the bottom.
I have one waiting in my garage (bought it during the holiday sale). I didn't see anything in Mountune's instructions about having to remove the bumper or any other body work, but it's not clear (to me) whether you drop it or lift it out -- if anything, seems like the latter. Let us know how it goes!
 


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redmoe

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Thread Starter #14
I will be making a video of the install. I should have the radiator mid next week as well as the spare bleeder cap and coolant I ordered.
 


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redmoe

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Thread Starter #15
OK so I got the radiator out it’s doable without taking the crash beam off and just having the car on ramps. Here’s a link to the video I may get it out. I think that it would be easier to remove the fan shroud from the bottom in hindsight to avoid damaging the radiator fins getting it out.

https://youtu.be/iS89u1D3_OM
 


Intuit

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#16
Good video Rod. Watched it at double speed. It'll be interesting to see how the Mountune radiator physically compares to the OEM. (Would be nice to get info on internal differences but obviously that may be a problem.) You're right, that radiator doesn't have a lot of depth. Looking at the radiator that's in the Escape, would tell us whether our OEM radiator was simply designed for the car, rather than the engine. Also, is it common for manufacturers to place the side tanks on the top/bottom now? Wonder whether there's any dis/advantages to the design. The flow-pipes though they can be more numerous, might be shorter? Just depends on the internal design. It'd be interesting to disassmble one of the known defective radiators. (which it sounds like it may be)
 


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Halifax
#17
Same thing happening here. While cruising, temps hover around 175-195. When sitting in idle traffic temps quickly rise to about 220-235. I shut it down and pull over if that happens as I don't want to risk it climbing higher and dealing with overheating issues.

Investigating fixes. Lower temp thermostat or bigger rad seems to be the route. Both seem like decently big jobs which I am not looking forward too.

Other than that, this cars been a joy.
 


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redmoe

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Thread Starter #18
It looks like our radiator C1BZ-8005-A is built for the car rather than the engine. The Escape has a different part number with the inlet and outlet on the sides. The fitment list for either the fiesta st or escape radiators is only for those cars. I am guessing that the body design does not allow for common use radiators.
 


Intuit

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#19
Modern thermostats typically have a gradual open... starting to open at one temp, and fully open by another temp. I'll have to lookup the specs in the service manual as the forum posts don't accurately specify both temps.

Based on the table in this thread...
http://www.fiestastforum.com/forum/...on-temperature?p=112346&viewfull=1#post112346

Ambient Air Temp 80°F and Coolant Temperature vs Radiator Fan Speeds are:
180°F 0%
190°F 3%
210°F 3%
215°F 15%
220°F 25%
230°F 100%

So our engine fan doesn't even consider going full tilt until it's 230°F. The way Pulse Width Modulation duty cycle works, I'm not entirely sure that a 25% duty cycle actually correlates to 25% of maximum speed. Regardless, a sudden jump of 75% is huge. Curious what their reasons are for taking such an utterly passive approach toward controlling engine temperatures? (suspect it's purely about fuel economy - electric fan places a large load on the alternator - which negatively impacts fuel economy)

The changes for higher ambient air temps can be described as subtle at best.

 


Last edited:
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#20
Mines a 2017. It’s getting stuck stationary for 5 plus minutes that drives up my coolant temp. Then if I start hitting more traffic there isn’t enough time to get air flowing through the radiator.

Is 202 you peak or is that your average? How long are your drive durations? Sorry for all the questions the reason I ask about the duration is if I drive for about 30 or under my temps are like yours. If I drive longer or only let the car rest for an hour the temps get higher. Just trying to figure out if I need to go ahead and get an upgraded radiator.
202 is my peak temp.

When cruising around town or even on the highway they'll stay between 190-195, maybe on a real hot day 200 tops but nothing higher than that cruising.
 


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