Ecoboost Cooling issues Valuable info

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joezek

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Recently bought a very well dealer maintained 2017 EL King Ranch. Before installing upgraded ECM tunes I needed to make sure the cooling system was right.

Well this thing was running about 210-215 all the time (Florida 90's weather).

I swapped the factory 190 thermostat with a Motorad 170 and kept the same brand new looking coolant. Well, temp stayed almost exactly the same 210-215.

I picked up a coolant tester and saw that it had almost 100% pure antifreeze that was off the scale and freeze temp below -50 degrees.

I diluted it to about 10% coolant and rest water, water is the best there is for cooling. I added Motor Medic coolant additive that lubes the water pump and prevents rust in the system. Now the temps dropped 15 degrees, but still @ 195. Basically the thermostat is always wide open, but not quite flowing enough.

Did research, found the Reische brand thermostat is totally different, flows volume just like the factory one. I installed a Reisch 170 thermostat and now the temps are a consistent 172-180. MAJOR improvement from the 215 where I started. BUT still the thermostat is running wide open above 170, and is basically useless because the coolant in the radiator never gets a chance to cool down. If I'm stuck in traffic and everything gets hot, it'll be like a runaway train and continue to keep getting hotter.

My final thoughts are the stock radiator (at least mine with 200K miles) can't handle a 170 thermostat, it's a complete waste of time. But I'm replacing it with an SPD 180 thermostat which should be the perfect one for a factory radiator. Looks like the SPD will flow just like the Reische and the Ford one, just at the lowest temp the stock radiator can handle.

This summer, towing the boat every well will be the real test. Next upgrades will have to be improved radiator and tranny cooler. That big ass intercooler brings a lot of heat in front of the radiator, makes things complicated.

Joe
 

Fasttimes

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Thanks Joe, good info. Do you have the HD package already? What temps do you think are "normal"?
 
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joezek

joezek

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HD Packing? I'm not sure what you mean. When I get the SPD 180, I'm expecting it to stay much more consistent near 180. Right now it's all over the place. And with the motorad 170 it just stays around 195-200.
 

ZigZagFred

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Hi Joezek - I can't help but wonder how you were convinced to believe that water is the best coolant one can use. Water boils (and turns to steam) at 212 degrees F. Quality coolant has a MUCH higher boiling point and is therefore a much better coolant. Additionally, most name-brand coolants also do a good job of lubricating your water pump and keeping your passages clean.
 
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joezek

joezek

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Because if you follow the drag racing community, you see they all tell you the best coolant there is, is pure water based on the fact that it has the lowest surface tension, which transfers heat the quickest to and from the radiator.

Some drag strip even require water only and do not allow antifreeze on any Vehicles driven on their track. That's because the antifreeze will ruin the track surface it takes much longer to clean up. And the racers don't care because it isn't as efficient as pure water.

As far as boiling point.... The reason we have radiator caps and the cooling system pressure is set around 16psi is to raise the boiling temperature of the water or whatever you use.

The best combination is to use as little antifreeze as you can based on your local temperature and then add supplements to the water to lubricate the pump. There's plenty of articles written about it
 

99WhiteC5Coupe

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HD Packing? I'm not sure what you mean. When I get the SPD 180, I'm expecting it to stay much more consistent near 180. Right now it's all over the place. And with the motorad 170 it just stays around 195-200.



An engine coolant thermostat is not designed to permit the engine to run at a specific temperature, once fully warmed-up.

It is designed to open at a specific temperature (often 180 - 195 degrees), which ensures a qucker warmup, which helps fuel economy, HVAC heat output and engine emissions.

If an engine is designed to operate at a certain temperature (such as 195 - 205 degrees Fahrenheit), a lower temperature rated engine thermostat will simply remain open once the engine coolant reaches the thermostat rated opening temperature (such as 170 or 180 degrees Fahrenheit). It will NOT enable the engine to run cooler that it is rated to run.
 
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joezek

joezek

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Here's a bit of knowledge that you can't learn from reading the owners manual or the label of the bottle of antifreeze....

Important technical info about ANTIFREEZE and why you need water

The point of my post is very simply to point out that too much "coolant or antifreeze" vs water it will hurt your engines ability to transfer heat to the radiator- that's it. You make your own decision on running the recommended 50/50 or not, my whole point was to say that some morons actually run 100% coolant which is the worst thing you can do. In my case I choose to run a lesser amount antifreeze and supplement the lubricant and corrosion with an additive. It works perfectly, it's been in the 90's every day the last few weeks and the temps are consistently staying around 177.

Even Prestone antifreeze has a technical link on their website saying how they have a standard 50/50 one size fits all recommendation BUT for warmer climates a 70/30 water/coolant is the ultimate ratio because of the ability to transfer heat and still lube the pump/prevent corrosion.

The entire reason of the post is to show from real experience this time and on other vehicles I've had that before you waste lots of $$$$ replacing thermostats, water pumps, radiators, fans, fan clutches----before you do any of that, make sure you check the amount of water/antifreeze in your engine. If you live in an area that freezes than obviously you want more antifreeze.

And if you paid any attention to my original post, I said that putting a Motorad brand 170 thermostat made no difference in cooling the engine down -AT ALL- but then changing the ratio of water/coolant dropped it 15 degrees..........which was the main reason I wanted to share my experience with everyone- not to have someone who disagrees feel the need to derail my actual experience with a bunch of arguments.

And don't even try to spin this into a bunch of drag racing comments- you can just exit this whole conversation.
 

roard

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Super interesting your feedback, thank you for all the details!
I had a bit of the same problems with my 3.5, the 170 seemed too fair with the original rad.
I also think that the SPD 180 will be more balanced to keep stable temperatures.
You did well to check the liquid ratio, 100% antifreeze is a real furnace.
Keep us posted this summer with the boat, it's going to be the real test.
Next step for me too: rad and trans cooler upgrade.
 

Calidad

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Aftermarket thermostats are well known across all brands to be very problematic so keep that in mind. They just seem to have a high failure rate. My 2019 had a bad factory thermostat just got the updated new one made a huge difference in both transmission and engine temperature far lower temps and much quicker to cool when it did see minor temp spikes
 

NorthernExMax

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Here's a bit of knowledge that you can't learn from reading the owners manual or the label of the bottle of antifreeze....

Important technical info about ANTIFREEZE and why you need water

The point of my post is very simply to point out that too much "coolant or antifreeze" vs water it will hurt your engines ability to transfer heat to the radiator- that's it. You make your own decision on running the recommended 50/50 or not, my whole point was to say that some morons actually run 100% coolant which is the worst thing you can do. In my case I choose to run a lesser amount antifreeze and supplement the lubricant and corrosion with an additive. It works perfectly, it's been in the 90's every day the last few weeks and the temps are consistently staying around 177.

Even Prestone antifreeze has a technical link on their website saying how they have a standard 50/50 one size fits all recommendation BUT for warmer climates a 70/30 water/coolant is the ultimate ratio because of the ability to transfer heat and still lube the pump/prevent corrosion.

The entire reason of the post is to show from real experience this time and on other vehicles I've had that before you waste lots of $$$$ replacing thermostats, water pumps, radiators, fans, fan clutches----before you do any of that, make sure you check the amount of water/antifreeze in your engine. If you live in an area that freezes than obviously you want more antifreeze.

And if you paid any attention to my original post, I said that putting a Motorad brand 170 thermostat made no difference in cooling the engine down -AT ALL- but then changing the ratio of water/coolant dropped it 15 degrees..........which was the main reason I wanted to share my experience with everyone- not to have someone who disagrees feel the need to derail my actual experience with a bunch of arguments.

And don't even try to spin this into a bunch of drag racing comments- you can just exit this whole conversation.
In my dakota I used to run 70/30, cast head and block just soaks so much heat and those magnum engines get real hot. I would be a little worried with about 10% antifreeze, but i applaud you for understanding that the WATER in coolant does the cooling, not the antifreeze. 50/50 ratio, for all out there, is good for -20F. 30/40% antifreeze is usually good for 0F, and obviously we all know water is fine by itself until 32F.

The largest improvement to be gained in cooling efficiency is relocate the intercooler away from in front of the radiator (if it is right in front of the radiator). This will stop the intercooler from heating the radiator. Larger radiator will change nothing if the intercooler is still cooking the radiator there.
 
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