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Adding coolant when level is low?

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Old Jul 28, 2013 | 08:02 AM
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Default Adding coolant when level is low?

I was cleaning my engine bay this morning when I decided to just check my fluid levels (oil, coolant, windshield washing fluid, etc.). I noticed that my coolant level was right at the "low" mark on the reservoir. I have not had any overheating issues nor do I see evidence of a leak anywhere. I have an 09 so I don't think I have any water pump issues (no telltale pink stuff splattered about). In prior cars, as a routine check, I'd always make sure the coolant levels were right in between the low and full marks, if not closer to full, especially during the hottest part of the summer.

Should I go buy some coolant at my dealership and top it off? Have any of you checked your coolant levels?
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Old Jul 28, 2013 | 08:31 AM
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its fine as is, but topping it off would be ok

for some reason, anytime you fill the coolant level anywhere to near the halfway mark, it'll come out through the overflow tube and make a horrible mess in your engine bay. I believe its poorly design by toyota. I just top off till halfway, drive a bit, and then clean all the overflow. Usually my coolant stays around around the quarter mark
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Old Jul 28, 2013 | 09:04 AM
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that is normal as some coolant dose evaporate over time. you can just top it off.
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Old Jul 28, 2013 | 09:50 AM
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As others have said coolant evaporates over time. From the wise words of lobuxracer, when my coolant was low he told me I could add distilled water (must be distilled) to bring it back up to full. My dealership confirmed that my water pump is intact and there are no leaks.

So you can simply add distilled water: https://www.clublexus.com/forums/is-...leaking-4.html
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Old Jul 28, 2013 | 10:07 AM
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Thanks for the link and advice Vijay!
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Old Jul 28, 2013 | 11:05 AM
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I was wondering the same exact thing before reading your post vbb. Great advice!
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Old Jul 28, 2013 | 12:47 PM
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I just added a little water, mine was the same
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Old Jul 29, 2013 | 11:42 AM
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Just FYI, my 09 had a leaking water pump. I believe the issue affected mostly 08's, but 09's as well. They fixed it with the 10 models. I'd keep an eye on it.
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Old Aug 5, 2013 | 08:41 PM
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I agree that it seems to be able to evaporate. I had an issue like that with my previous car (Audi S5) which I had pressure/leak tested because coolant was disappearing. They never found anything, and just said it was certainly possible to have it evaporate.
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Old Aug 6, 2013 | 12:00 PM
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09 isfs still have the water pump issue. That was not fixed till the 10s. If it is original it is probably leaking. It starts to leak from a seep hole behind the pulley. Use a small mirror to check it. If it isn't leaking then the coolant is just evaporating but be sure to check the water pump for sure.
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Old Mar 22, 2014 | 09:56 PM
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I was checking my coolant level today with the car off, and noticed it was sitting between "low" and "full". I also noticed that when the car is fully warmed up, the coolant level goes up to full. I didn't notice any dried pink stuff in the engine bay.... does this mean I can add more distilled water? Or should it be coolant?
Attached Thumbnails Adding coolant when level is low?-20140322_175834.jpg  
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Old Mar 23, 2014 | 10:47 AM
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The marks are cold marks. I fill mine until the full mark when cold. You can use distilled water or coolant, your choice, it won't be a big deal either way. Water does conduct heat better, so adding water does slightly improve the cooling capacity of the system at the expense of lowering the boiling point.

In the old days of mix it yourself coolant, Toyota recommended 50/50 distilled water to their red coolant. I run 80/20 distilled to coolant in my Supra because it makes the engine more tolerant of inadequate octane in the fuel. It was a huge problem in California because my gas mileage went from 18 mpg to 12 mpg when they reduced premium from 93 to 92. I changed my coolant ratio from 50/50 to 80/20, installed a high pressure radiator cap, and got my gas mileage back. When they went to 91, I was permanently screwed and had to mix 4 gallons of 100 octane race gas with 14 gallons of 91 to get my mileage back. I ran the numbers, and it was actually cheaper to run the race gas mix than it was to suffer the mileage loss.

None of this should be any problem at all on the 2UR-GSE. It was designed and calibrated to run on 91 from the factory.
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