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Engine Coolant HOT

TemecFist

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#21
T
If you buy 50/50 coolant and want to make 70/30, you'll have to do a little math to arrive at the correct amount of water to add. And you can't trust 70/30 for use in subfreezing temperatures.
Buy an antifreeze hydrometer, remove antifreeze (overflow), replace with distilled water, and test it. Keep doing this until you get to your target mixture. Your target mixture will be the lowest temps your car will ever see. THAT, is the least amount of coolant you can use. A mixture with 10% antifreeze is still good for anti corrosion and to lube the water pump.
 


Old Mike Emerson

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#23
Since this just started during hot months I would suspect the Thermostat, also I would look to see if your intercooler, A/C condenser and radiator are clogged with dirt. I would go to the local hand wash car wash place and use the high pressure hose to clean them out, I do this once a year whether I'm having problems or not.
 


Dash

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#24
Sorry my friend, but you're wrong. I run a 10/90 mix in my track car, and it definitely helps. I've never had my coolant temps go above 220*.....ever.
Even the GTR comes with a mix of 70/30, unless you have the cold weather package, then the mix is 50/50.
Have you ran the 10/90 mix car on the streets? On the track, you're going at high speeds which helps cool the coolant in the radiator faster. Not sure if you'd get the same results from stop and go traffic.

Not saying I'm not wrong but using just your track car 10/90 mix as evidence is not all that dependable.
 


green_henry

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#25
Have you ran the 10/90 mix car on the streets? On the track, you're going at high speeds which helps cool the coolant in the radiator faster. Not sure if you'd get the same results from stop and go traffic.

Not saying I'm not wrong but using just your track car 10/90 mix as evidence is not all that dependable.
I can vouch for distilled water making a big difference. I don't have to worry about freezing, so I run distilled water + Water Wetter. I flushed it thoroughly with BlueDevil when I switched over (just because).

That said, it sounds like something else is going on as well (maybe an air pocket?).
 


gtx3076

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#26
A 30/70 mix (30% water 70% antifreeze) will protect down to 5*. If it's colder than 5*, and your still overheating.....you have serious issues somewhere else.
Good to know. It might get into the teens on the rare occasion here in Texas and I got a jug of distilled water sitting in my kitchen...
 


M-Sport fan

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#27
Tuners also have access to this already. It’s not a great fix for the problem imo. I have so much peace of mind after installing the mountune.
I did not mean, nor imply, in lieu of an upgraded aftermarket radiator (which I WILL get sooner than later), just as a holdover until one can be installed.

But it can still help even with a Mountune installed, if one gets caught in a 'parking lot' type traffic jam when one sees the temps creeping up, you can run the high speed fan for a couple of minutes to bring it back down, then switch it off.

One does not have that direct temp control with a tuner's SET, one temp fan turn on.
 


XR650R

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#28
Stupid question, I’ve read it somewhere before but how do you get the 70/30 mix? And what kind of water do you put in it again?


Sent from my iPhone using Tapatalk
No stupid questions here. New car, new stuff to know.
I hope it's not a bad thermostat. I hear they're a bitch.
 


Dash

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#29
Did some research on using 100% distilled water and you all are right that it does help lower the temperature.

I was running pure 100% distilled water when I was diagnosing my thermostat problem and I just didn't see a difference between distilled water and 50/50 in normal driving. Just my own experience...
 


TemecFist

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#30
The best thing to remember is that coolant does NOT cool.
Pure water will do the best job.
However, you need the additives to provide lubricant and corrasion resistance.
Exactly this!!!!! It's called antiFREEZE, not antiOVERHEAT. lol
 


TemecFist

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#31
Have you ran the 10/90 mix car on the streets? On the track, you're going at high speeds which helps cool the coolant in the radiator faster. Not sure if you'd get the same results from stop and go traffic.

Not saying I'm not wrong but using just your track car 10/90 mix as evidence is not all that dependable.
Yep. I sure have. Car has never overheated. Even in LA stop and go traffic, when it's 110* outside. My car has never been in limp mode, not once. Not on the track, not on the street.
 


TemecFist

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#32
Good to know. It might get into the teens on the rare occasion here in Texas and I got a jug of distilled water sitting in my kitchen...
Sorry my friend, this post was wrong. It's 70% water, and 30% antifreeze. That is still good down to 5*. I initially wrote that wrong
 


Jabbit

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#35
If you don't want to mess with measuring, get a 3 gallon empty jug and mix 2 gallons of distilled water with 1 gallon of coolant (not 50/50 mix) and you'll end up with 67:33 ratio.
 


Intuit

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#37
I suspect the manufacturers intentionally run the direct-injection engines hotter in order to clean them up.

Previous car had a known bad thermostat and thermostat bypass valve which made it over-cool. I liked it since it was a bi-metal engine plus had more get-up and go. Downside was, years of running cold eventually clogged up the catalytic converter with ash.

Blocked off part of the radiator on the motorcycle because the higher engine temps cleanup the cylinders, plugs. I've since figured out that a lean mixture was mostly responsible for fowling them, but still intentionally run it hotter as this has proven beneficial.

Bottom line, understand that the manufactures may be running higher-end temps on purpose; and messing with that may have unanticipated consequences for the long term.
 


Capri to ST

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#38
I suspect the manufacturers intentionally run the direct-injection engines hotter in order to clean them up.
Bottom line, understand that the manufactures may be running higher-end temps on purpose; and messing with that may have unanticipated consequences for the long term.
You make a good point, that may well be the case.I have read that manufacturers manipulate engine temperature for a variety of reasons now, including emissions and as you say possibly to keep a direct injection engine cleaner by letting it burn hotter.
The tech writer in the BMW magazine was saying this a while back. He said because this temperature manipulation is being done, car manufacturers keep the gauges at kind of a middle point, because if people saw all the fluctuations it would make them nervous. However, a lot of people on here are plugging in their APs and seeing these fluctuations, especially on the high end, and it may be worrying them unnecessarily to have this extra information. I realize that some cars are clearly having overheating problems, I'm just wondering if some people think they have a problem when they don't actually have one.
 


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M-Sport fan

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#39
^^^I agree with BOTH of you above, and I don't care as long as the temps do not 'runaway', and climb up to the point of dinging/limp mode, and warping the head/blasting out a head gasket.

WHY I am paranoid when I see the sitting still/idling in traffic temps climb up past 212, thinking that the temps will keep on climbing, and then turn on the AC so that the high speed fan starts to bring them down to 190 (or slightly lower once moving). [wink]
 




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