Tap or Distilled H2O for Coolant?

[ZachFr]

I'm about to do a coolant flush and am not sure if I should use distilled water or tap water to both clean out the system and to use for the 50/50 mix. Any suggestions?
Thanks!

[4Jenna]

I always use distilled water.

[ZachFr]

That's what I was leaning towards, thanks!

I just came across this site and though it was pretty helpful...
http://www.mikefordmustang.com/writeups/coolant_flush/flush-coolant-on-mustang.php

[Mr. Austin]

If your just flushing then you can you tap. It wont hurt anything. If you running it with distilled for a while the tap water will build up calcium and other junk do to all the minerals. This happens more so in the aluminum radiators due so their texture. Flushing you can use a garden hose wont hurt anything. Running in the radiator? Defiantly use distilled. Hope that helps.

[BurnTire]

60/40 water/anti with redline water wetter. Make sure all the air gets burped out of the system after filling.

[ttocs]

I found out last year why to use DI. I went to do a simple intake swap and found out that some of the bolts that hold the lower to the head, end in the coolant channel. If RTV or a sealant is not properly used(or has worn out) and tap water is used, those screws will rust from the bottom up. The first bolt I went to take out of the lower snapped as soon as I pushed on it. It was such a rusty corroded mess that after $120 in different back-out-bits I ended up buying new heads.

[ZachFr]

I ended up using distilled for the entire flush and refill... Next time I am going to take a hose slowly filling the radiator with the engine running, and draining it at the same time, then rinse it with distilled a few times. Sounds much easier than what I did (Completely filled, then ran the engine, then drained with distilled, about 7 times). It would appear this method is safe to use?

Not to bad for the first Radiator flush I've done, though. Haha.

[BurnTire]

I ended up using distilled for the entire flush and refill... Next time I am going to take a hose slowly filling the radiator with the engine running, and draining it at the same time, then rinse it with distilled a few times. Sounds much easier than what I did (Completely filled, then ran the engine, then drained with distilled, about 7 times). It would appear this method is safe to use?

Not to bad for the first Radiator flush I've done, though. Haha.

It is always good to run the heater on full blast when filling to ensure you get flow through the heater core.

To get a true flush you would need a shop with a flush machine, but I never had a shop flush on any high mile car I have owned. I would just change it like you did.

[Torchmach]

I have allways been a believer in using distilled water in the cooling system, and battery. The water around Phoenix is very allkline, and a lot of clorine is used by some muncipalities during the summer months. I figure that distilled water is cheap insurance at the least.

[ZachFr]

It is always good to run the heater on full blast when filling to ensure you get flow through the heater core.


Didn't think to do that... Will do next time though. But even so, definitely a step up from what was in there before lol. It was gettin' dirty.

[IMSHAKN]

For what it's worth I typically flush everything with the hose containing an inline filter and then fill it with 60/40 mixture of distilled water/coolant and then top her off with a bottle of water wetter.

I got lazy this summer and didn't flush mine like I said I was going to... pretty sad as I've already got the distilled water, a bottle of water wetter, and two bottles of Motorcraft Gold all ready to go. Maybe I should actually do this sometime soon now that you've reminded me.

[Jacostang]

I buy the 50/50 mix and dont really know what kind of water they mix it with from the distributor so I hope they use the right kind of water...

[ZachFr]

For what it's worth I typically flush everything with the hose containing an inline filter and then fill it with 60/40 mixture of distilled water/coolant and then top her off with a bottle of water wetter.

I got lazy this summer and didn't flush mine like I said I was going to... pretty sad as I've already got the distilled water, a bottle of water wetter, and two bottles of Motorcraft Gold all ready to go. Maybe I should actually do this sometime soon now that you've reminded me.

Filter on the hose? Not a bad idea. And you're welcome, better get on that :pinkthumb:

[ZachFr]

I buy the 50/50 mix and dont really know what kind of water they mix it with from the distributor so I hope they use the right kind of water...

I'd hope they do. I read somewhere the coolant is made for tap, but I just didn't feel comfortable using it. I got the straight coolant for buy (1) get (1) free @ wally w/ mail in rebate, so definitely cheaper than going for the 50/50. :Bucktooth:

[6-Speed]

It's always better to use distilled water since the minerals in the hard water here can decrease the effectiveness and shorten the life of the coolant additives that inhibit corrosion in the engine coolant passages, water pump and radiator.