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Drained Tap Water In Coolant and Refilled

5.7K views 35 replies 14 participants last post by  XtRaSlo  
#1 ·
Some mechanic drained my coolant when replacing the starter in my ‘06 Corolla. Then he topped off off with water and drove it for a little bit. The next day I drained all the coolant and refilled it back with coolant.

Is it going to be fine or do I need an actual flush?

Also wrong forum, can someone move this?
 
#4 · (Edited)
That’s the right answer but I keep reading dealerships top off coolant with regular water regularly so how big a deal is it?

Edit - I spoke to the mechanic and he said a hose that contained coolant needed to be removed to get to the starter so that’s why some coolant was removed. And he said we didn’t add enough water to make a difference in the coolant so it’s fine.

The car has 200k miles so it probably needs a coolant flush regardless I guess.
 
#3 ·
It really comes down to what exactly that mechanic did. Did they drain a small amount of coolant and top it off with (what ever type of) water? Did they do a full drain and refill with only (what ever type of) water? Why did they mess with the coolant anyway if they were replacing the starter? Was there some other reason the mechanic was messing with the coolant? Whole lot of questions.

If one wants to be safe. If one doesn't know exactly what the mechanic did or what water they used. Then do a full coolant system flush and replace with the proper coolant fluid mix/type recommended by Toyota for the Corolla. Then send the mechanic the bill and hopefully they'll own up to their mistake and cover the cost of the flush/proper coolant.
 
#33 ·
it's probably fine. for a little peice of mind, you can get a coolant tester, right? one of those bulb shaped things, I think it measures specific gravity

Prestone AF-1420 Antifreeze/Coolant Tester
I think OP is more concerned about logt-term effects of tap water and not reduced freeze/boil over numbers. Distilled h2o is like $1/gallon at thr dollar store, shame the mechanic doesn't keep some on hand (this issur would bother OCD me :(
 
#10 ·
You’ll be fine. You did a drain and fill with I hope the appropriate antifreeze. Why the mechanic drained some and refilled with regular water is beyond me. But in the grand scheme of things, it won’t matter. If you feel perturbed enough, just do another drain and fill in another 15k or so miles for some more peace of mind.
 
#11 ·
How many gallons of coolant do these corollas hold? I added a gallon but the reservoir tank got completely empty after I filled it up all the way up so I refilled it for a second time and now it’s been getting close to empty again. The radiator seems full though.

Did I just not add enough coolant the first time?
 
#16 ·
Look up videos on YouTube on how to burp your radiator after drain and refill of anti freeze. Basically:
1. Jack up the front of the car as much as possible
2. Fill up the radiator to the neck and then the reservoir to the max line. Leave the radiator cap off
3. Turn the temperature knob to full heat and have your blower motor set to max speed
4. Turn on the car and let it run
5. Occasionally rev up the engine up to say about 2,000RPM and hold it there for l10-15 seconds. Rinse and repeat multiple times
6. Keep an eye on the reservoir and make sure that it doesn’t drop below the min line
7. Shut the car off after 20 mins or so and lower it.
8. Top off the radiator and put the radiator cap on
9. Let the engine cool down. Top off the reservoir as needed

This method will make a mess when the radiator “burps”. You can buy a spill free funnel if you so prefer
 
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#18 ·
Well the car is what 15 years old? Have you flushed it before or even serviced the coolant? If the answer is yes you can just drain it and refill it with out a flush. If the answer is no than the car is long over do for proper servicing which in this case should include a flush.

I like to use a large bottle of SHOUT laundry stain pre-treater for flushing. Why? It is gentle to aluminum, brass and iron. It will clean any grease, oil, grime with no risk of harming anything. It does not have any acid or alkali in it that can eat into already corroded aluminum!

Drain Block and reverse flush everything.

Most people take the thermostat out to make the flushing and back flushing easy to do and install a new thermostat and radiator cap at the same time! Take reservoir off and clean it out too. Refill with Toyota Ultra Long Life Pre-Mix or OTC equivalent.
 
#21 ·
P.S. Never take your car to that shop ever again! I would not fault a shop in the USA using a universal all makes all model generic coolant even though that is wrong. On the other hand any shop in the USA that would use tap water in a cooling system is not to be trusted. A coolant has to be designed for tap water and the last time I saw anything like that was in Europe and that was decades ago. In fact back in the day Daimler Coolant was designed for Germanys hard water. Most US and Asian coolants are designed for distilled water aka deionized water. In fact that is why so many modern Asian coolants come in pre-diluted 50/50 ready to use to keep people from messing things up!
 
#22 ·
The starter service doesn’t require removing any cooling line. You do need to move the radiator shroud down a little and your clear. Everything can be disconnected under the car and removing the lower bolt. Then, the top bolt comes off and bam.. your golden. Reinstall. It is a easy job. No clue how the tech messed up.

It is very possible that the tech instead did this: he removed the radiator shroud and took the whole shroud off of the car just to get to the starter. This can very much cause you to lose some coolant because the shroud has the expansion tank built in. If you remove the shroud you can leak from expansion tank, hence, loosing some coolant. An overblown situation is what I would call it. However, if they put tap in the car, remove the expansion tank (assuming they put it there) fluid and fill back with factory 50/50. But! If you have already ran the car thru 2 or more heat cycles, you already mixed the tap water in the system.
So many sloppy Joes.


Sent from my iPhone using Tapatalk
 
#23 ·
The starter service doesn’t require removing any cooling line. You do need to move the radiator shroud down a little and your clear. Everything can be disconnected under the car and removing the lower bolt. Then, the top bolt comes off and bam.. your golden. Reinstall. It is a easy job. No clue how the tech messed up.

It is very possible that the tech instead did this: he removed the radiator shroud and took the whole shroud off of the car just to get to the starter. This can very much cause you to lose some coolant because the shroud has the expansion tank built in. If you remove the shroud you can leak from expansion tank, hence, loosing some coolant. An overblown situation is what I would call it. However, if they put tap in the car, remove the expansion tank (assuming they put it there) fluid and fill back with factory 50/50. But! If you have already ran the car thru 2 or more heat cycles, you already mixed the tap water in the system.
So many sloppy Joes.


Sent from my iPhone using Tapatalk
I agree!
 
#32 ·
Well in this case the coolant flows only really after the thermostat opens. Some cars have significant bypass but not all. So once you heat the car up enough that the thermostat opens the coolant in the block and in the radiator and reservoir begin to mix. Prior to them mixing it is easy to drain one and refill with out affecting the other parts of the system. Once they mix though any contamination will have mixed with the entire system so then the entire system would need to be purged and refilled!