Tap water in engine coolant tank?
 

So the crappy story is my girlfriend took her car to a service station and let them fill some engine coolant fluid(which was very low in her car). However after she back she told me all the guy did is filling some tap water into the coolant tank.

I read an article telling all about the horrible stories of filling tap water as coolant. Are those true.

If so, is there an easy way that we can fix this problem? can we just buy some coolant fluid and add it into? Or do we have to do the flush and refill work?

Thanks a loooooooooot!

it's fine. if you're super worried about it just drain and refill the coolant system

Tap water will cause corrosion over time due do all the mineral within it.
Flush it few times and replace with distilled water.

Wait... Did they fill the cooling system with water only, or water and coolant? And did they just add a (relatively) little, or much more?

There is a 50/50 premix, so tap water should be fine. It depends how low is the coolant level when they add the tap water.

It also depends on your tap water ;)

Where I live we have very soft water...about 5ppm .....neutral pH

I have lived places that it is hundreds of times higher and acidic, so here tap water is almost as good as distilled...and the other place ate the copper pipes out of the house in about 4 years :)

Like Dan said, it depends on the water quality. Although I'd be leery of drinking water that was not safe to put into a radiator.

If they put in only water, and you live in a cold climate, I'd worry about the antifreeze being diluted this coming winter. You can get a coolant hydrometer for a few dollars and check that.

I'd also worry about why the coolant was low. If there's a leak, best to fix that rather than just keep topping up.

Ken

dont listen to mochie. he does not know what hes talking about.

Lol! i thought most everybody blocked him by now?

as others have said, it's not advisable to pour tap water into the cooling system but I doubt it's going to break thing either.
If it were me, I would flush the system just to be safe but then again, I'm paranoid like that.

If it was just a bit of tap water to top off the overflow but there was coolant (50/50) in the majority of the system, you should be fine.

Does this forum have that capability?

Monchie is one of the last people I'd want to killfile, but there are a couple of others.

Ken

Tap water is all people use when they use concentrated instead of premixed. Your fine but as others said make sure it's not all water. The hydrometers you buy will even tell you on a temperature scale how low your fluid is good for before it will freeze.

In all of my time here I only have one person on my block list. Guess who it is.



OP, it will probably be fine but like others have said, it's not a good idea to do on a regular basis and any leaks should be fixed properly.

fixed

Thanks for your concern.


I'll look into this situation, thanks.

No matter where you live there are impurities in your tap water... there is no if/ands/buts about it. The reason we used distilled water for radiators is because a few things need to be taken into consideration. First, tap water naturally comes to a boil faster than distilled water, not because the boiling point of the water is lower, but the volume of water against the impurities and contaminants of the water is far lower.

Also consider the mixing of metals when going from your radiator, to your hoses, through your motor, pump, etc. Tap water can have a range of pH which could cause corrosion and cavitation to pumps and metals. The use of an additive, namely glycol, increases the pH of the coolant and helps prevent the dangers of a low pH cooling system.

Lastly, tap water has more of a risk for carrying electrolytes picked up from plumbing sources. In theory, electrolytes can wreak havoc when it comes to mixing metals through electrolysis.

Now again, the above is all "in theory" ... I have heard stories of people running tap water in their rads for 30+ years without issue. Really all comes down to where you live like others have said .... but nevertheless ... why not just err on the side of caution and grab a couple jugs of distilled water from your local grocery/drug store? Surely you can spare a few bucks.

Your radiator is filled with more impurities than any city tap water would be. Just saying....

The glycol will change the boiling point (not by much) but more importantly it has superior heat transfer properties and lowers the freezing point. Most engine coolants run around 212 deg F anyway. I don't know if rotarys run hotter or not....


Distilled better than tap - yes. Any reason to worry about tap - no. Most important is you have a 50:50 or close mix and your level is good.

Stop freaking the OP out lol.

This is the truth! I would also add to ensure your system is pressurized. Which means a good radiator cap and no leaks. A pressurized system raises the boiling point significantly.

I would guess that well over 90% of the automobiles on the road have tap water in the cooling system. It's really not a big deal.

That's what I've always done. That's also all that I've ever seen garages use. Never any problems.

FWIW, I still fill my tires with air, not nitrogen.

Ken

You're DOOOOOMED!!! :SHOCKED:

We're enthusiasts here. We would never use anything but deionized water or a pre-mix 50/50 that already contains deionized water. As others have said even the best potable water contains some minerals. Sure, in the 70's we just used tap water, but thankfully we've evolved. ;)

The problem with using distilled water in the radiator or nitrogen in the tires is that nobody really sees that, so we don't get the image and the reaction.

I made a fuel cap hook, so the cap won't dangle against the paint. My friends all roll their eyes and say that the cap is not going to damage the paint. They're right (not that I'll tell them) but I get the proper OCD image across.

They fall in line pretty easily when I tell them no eating or drinking in the car. :)

Ken

seriously, no eating and drinking in the car. thats how I keep my interior almost pristine.

That's what my Hondas are for.

Easy to enforce if you have a fuel cap hook, a color-coordinated cover on your EZ-pass and a somewhat deranged look in your eye.

Ken

Go ahead and throw tap water in your coolant system on the regular. Report back on the status of your internals and water pump after a few years. Minerals need to be mined like in StarCraft.

Wow monchie ...

Yes it does, sir.

Is one of the person's name start with "NYCGP" ...? :eek:

Fixed.

you CAN use 100% distilled water IF you added additives like Water wetter/ICE to lube seals and anti-corrosion, freezing is NOT a concern, AND you change it VERY often.

but to ensure "trouble free" operation, 30% is what I would use, minimum

That's the reason why you DON'T want any extra impurities. it's not like your engine will die right away, but I would change it out ASAP.

EG coolant is more about protecting the engine , and it's safer than the old skool stuff they use. Water's superior heat-carring ability is almost 2nd to none. EG is not going to raise the boiling point too much but if you run it at 50/50's boiling point for an extended period of time, your engine won't last anyway.

most of those "quick lube places" even some bigger name garages usually just fill it with water and send u off.

not trying to freak him out but, a properly maintained car will last longer (duh), it's funny that sometimes I visit my friend's garage, some cars pull in with overheating engines and busted radiator. I just asked him like when was the last time you flush your "engine water/coolant", the guy was like "huh? u need to change it? I thought it last forever?" and he has just 90K miles. His bill was like 5K, including complete engine rebuild.

I hate it when that computer lady Tell me "Not enough minerals" when I'm trying to rush. lol

I guess I've never kept a car over 36k miles before so I never worry too much about the 100k plus miles problems lol.

And no I never lease.

Not by a long shot. You're well up among my favorites, along with Monchie.

Never mind my water pump. You ought to see my kidneys.

Ken

Lmao time to flush them out!

Just to confuse the issue further, deionized water is much more corrosive than tap water, and it can't be pumped through copper or steel pipes. However, once you mix it with coolant, it isn't DI anymore.
The issue with hard water is mineral deposits.

If the internals are stainless steel the concern is stress corrosion cracking. Since you can't remove heat or pressure it's basically going to fail at a weak or botched weld regardless of the water type.

Flush which...my favorite members or my kidneys? :evil_laug

Ken

All alloys are prone to corrosion. Don't tell me otherwise because I know I didn't pay $12,000 for 11 credits worth of engineering chemistry, material science, and material strength FOR NOTHING.

^^ yes and no. Corrosion as we typically see it is the oxidation of iron. Remove an element of the corrosion triangle and it doesn't happen.

For alloys such as stainless steel it doesn't see typical corrosion as I pointed out it's prone to stress corrosion cracking caused by free chlorides within the water. Chlorides alone won't do it. Again think of it like a fire triangle in which you have heat chlorides and weakspots or high pressures. Remove one and you won't see corrosion in stainless steels.

181 credits of Engineering suggests to me so. I am no expert in radiators though so I don't know what material we are dealing with in our cars but I would not stress over tap water.

Whoa...what a relief, lol

not much chance anyone is going to pick up deionized water by mistake :lol2:

so to all you lab rats out there... if your car overheats while driving to work dont grab a box of deionized water to top it off :spank:

As far as I remember it's all just Iron and Aluminum

I don't study Engineering so I dunno but what I do know is the less impurities the better. Tap water is called hard water and it's bad for engines for a reason.

It's called hard water only if it's got a lot of minerals. Varies from place to place. NYC has very good water (product of pillaging the Catskills for it) that I wouldn't hesitate to use in a radiator, or even a battery. I've been in places in the western plains and deserts where the water was so full of minerals and alkalai that washing was difficult because soap wouldn't lather. Wouldn't put that in anything. Especially not me, if I could help it.

Ken

The water pump is made of aluminum.

You Gus are killing, can't stop laughing, you did not solve the problem but anyway the white bottle is written coolant only so maybe we must stick to the manufacturer's recommendations.

^Trying to get your post count up? ;) LOL

Aluminum is ver susceptible to pitting corrosion in chloride environments.

Yeah, we used to be pretty entertaining in the old days. But at least we haven't lost the skill of not solving problems. :)

Ken

I'm new in this RX world, bought the car in March 2014 and it's been a learning curve all the way, i used to be a Volvo only driver.