Best way to flush coolant?

[Bartman39]

And, while many mentioned that during a flush, some of the water remains behind in the block, yet not one person has mentioned the little bulb thing that sucks up some of the fluid to test for the correct mix (antifreeze tester)? Wow. They're like $2 And, it takes the guess work out of wondering how much water was left behind.

Dont think you have read all the post...?

Also with the method I indicated the amount of water in the block is marginal and anything over a 30% solution is fine it does not have to be 50/50 unless your in a very cold area and if so then simply adjust with straight coolant to get the mix to the ratio you want... Just have an antifreeze tester handy after the car has been ran enough to mix the solution... Uh not rocket science...

 

[CraigRT]

I would just drain, and refill until its full. The only word of caution is do not mix coolant types.

If using Dex-Cool, use Dex-Cool again. Same for Ethylene Glycol, etc. (Green)

If you do a drain/refill every few years you never have to worry about what is remaining in the heater core etc. I have been doing basic drain and fills as long as I can remember.

 

[brblx]

Wow, some people think those jiffy lube types of places use distilled water? Surrrrrrrrre they do.

And, while many mentioned that during a flush, some of the water remains behind in the block, yet not one person has mentioned the little bulb thing that sucks up some of the fluid to test for the correct mix (antifreeze tester)? Wow. They're like $2 And, it takes the guess work out of wondering how much water was left behind.

i didn't mention it simply because i just generally wouldn't tell someone to do it that way. i might myself, but if someone is coming to the internet for advice on changing out their coolant, i would advise the most idiot proof way that involves only adding mixed coolant to the vehicle. also the way to make bleeding the easiest is to just leave some behind and not try to manually backflush. so drain and fill. plus bleeding, of course.

also whoever said water doesn't lubricate the water pump, congrats, you're right. unfortunately, antifreeze does.

 

[Bartman39]

also whoever said water doesn't lubricate the water pump, congrats, you're right. unfortunately, antifreeze does.

And how does it do this...? The bearings of a water pump are sealed on both ends (tandem bearing set)... So the only time coolant would help is when the seal on the inboard side of the bearing goes south...? Also just to note the seal of the water pump is lubed by the internal grease inside the bearing area not the coolant... The coolant helps with heat removal but will help keep the seal softened if antifreeze is in the system as well, but does not lube the seal itself... Plain water does not do anything for the seal at all...

 

[Howard]

How does this sound:

1) Drain system
2) Fill with distilled water
3) Circulate (heater on, engine hot, etc.)
4) Repeat steps 1 through 3
5) Drain system once more
6) Add pure Dex-Cool in the amount of 50% total capacity (10.6 qt/2 = 5.3 qt)
7) Top off with distilled water

If I add straight coolant, will it be dissolved inside the cooling system? Or will it remain discrete with respect to the water?

 

[Bartman39]

How does this sound:

1) Drain system
2) Fill with distilled water
3) Circulate (heater on, engine hot, etc.)
4) Repeat steps 1 through 3
5) Drain system once more
6) Add pure Dex-Cool in the amount of 50% total capacity (10.6 qt/2 = 5.3 qt)
7) Top off with distilled water

If I add straight coolant, will it be dissolved inside the cooling system? Or will it remain discrete with respect to the water?

Should work just fine & yes to the first part of the question... BTW how many miles on this car...?

 

[Howard]

Should work just fine & yes to the first part of the question... BTW how many miles on this car...?

About 72 000 miles

 

[Bartman39]

72K miles...? Uh Dex-cool is good for up to 150K miles... Waste of time and money to change it now...?

Myself I dont like the stuff (Dex-cool) and switched my diesel over to the universal type (basicly yellow in color) and added like I had said a bottle of Wixcool to the system and that was about 30K miles ago and everything looks good... BTW did the flush like I had mentioned as well, but this was all done because of a water pump going bad... Talk about a different type of pump it drives off the cam gear and the fan is on a bearing/idler and has nothing to do with driving the pump...

 

[Howard]

72K miles...? Uh Dex-cool is good for up to 150K miles... Waste of time and money to change it now...?

Myself I dont like the stuff (Dex-cool) and switched my diesel over to the universal type (basicly yellow in color) and added like I had said a bottle of Wixcool to the system and that was about 30K miles ago and everything looks good... BTW did the flush like I had mentioned as well, but this was all done because of a water pump going bad... Talk about a different type of pump it drives off the cam gear and the fan is on a bearing/idler and has nothing to do with driving the pump...

GM recommends a 5-year/100,000km coolant replacement, at least for my car, which I am overdue for.

 

[Bartman39]

Some interesting reading for you too... Guess for your car they lowered the miles/km...? Your going by time not miles...

http://www.dex-cool.net/

http://www.sancarlosradiator.com/dex-cool.htm

http://consumeraffairs.com/news04/2006/08/gm_dexcool.html


BTW I have never read these articles till now but have known for some time Dex-cool is not a good idea if you want it to last...

 

[sleep]

youtube always has some tutorials.

 

[IcePickFreak]

Make sure you bleed the air from the system after re-filling it. Didn't see it mentioned and you don't want to forget that part.

 

[WackyDan]

Make sure you bleed the air from the system after re-filling it. Didn't see it mentioned and you don't want to forget that part.

I mentioned it... no bites. It is also one of the reasons you need to check your levels after a drive as the air works it's way out of the system...

Thing is... Some of these newer engines can remain air locked in some parts of the cooling system for a very long time...and that is the hazard.

 

[5150MyU]

So if you follow the manufactures recommended procedure you should have no problem?

 

[JCH13]

Thing is... Some of these newer engines can remain air locked in some parts of the cooling system for a very long time...and that is the hazard.

Source? What makes you say that? Seems like an awfully general statement to me.

 

[alkemyst]

Source? What makes you say that? Seems like an awfully general statement to me.

many FSM's are very specific about it, not sure what you are doubting.

Some engines even have high mounted bleed ports due to engine/car design causing an area air can be trapped.

Happened to me when I recently had work on my car done...driving along and about 10 mins later the temp guage pegged high yet their was plenty of coolant. I rebled it back at home and called the shop to let them know about it in case I had trouble down the line.

Fortunately everything was fine.

 

[Bartman39]

He is correct in what he is saying... It takes about a days worth of driving to get all the air out of my Dmax`s system if you drain the system... Also the 3.1-3.4 GM V6 engines have high point bleeds but they also sometimes trap pockets of air and it takes awhile to get it all out... Some of the early reverse cooling systems were just about impossible to get fully purged...

 

[JCH13]

I'd believe that any cooling system could remain air-locked unless you follow the FSM directions, both old and new engines. And I also agree that it can take a day or two to get all of the air out, but that's hardly a "very long time."

I default to "skeptical" whenever some random person on the internet (no offense intended WackyDan) makes such a blanket statement. It's not to be facetious, just skeptical. If it turns out that WackyDan owns his owns his own radiator shop, I'd believe him. If he had trouble bleeding the cooling system in his Corolla after it overheated from hauling rocks... I wouldn't put stock in his statements

 

[Zargon]

Wow, some people think those jiffy lube types of places use distilled water? Surrrrrrrrre they do.

LOL for real.

And, while many mentioned that during a flush, some of the water remains behind in the block, yet not one person has mentioned the little bulb thing that sucks up some of the fluid to test for the correct mix (antifreeze tester)? Wow. They're like $2 And, it takes the guess work out of wondering how much water was left behind.

this. I know atleast that dexcool advertises that it can be used with regular tap water.

I wouldnt worry about distilled water, and decent car has enough cooling capactiy that the slightly lower cooling ability of non pure water will not be an issue

Some interesting reading for you too... Guess for your car they lowered the miles/km...? Your going by time not miles...

http://www.dex-cool.net/

http://www.sancarlosradiator.com/dex-cool.htm

http://consumeraffairs.com/news04/2006/08/gm_dexcool.html


BTW I have never read these articles till now but have known for some time Dex-cool is not a good idea if you want it to last...

thats great and all, but I have taken 3 different GM cars with dexcool past the 200K mark. my grand am was put to sleep becasue the watepump seal went out and no one will do the job because its a giant PITA, and the cars wasnt in good enough shape(hit a deer with it at one point) to justify bothering

doing a drain and fill is cheap, so I just do it once the coolant visually shows signs of aging. which is usually more than 2 years, but less than 5.

 

[alkemyst]

I wouldnt worry about distilled water, and decent car has enough cooling capactiy that the slightly lower cooling ability of non pure water will not be an issue

It is more about the minerals on the metals than cooling capacity.

 

[IcePickFreak]

I mentioned it... no bites. It is also one of the reasons you need to check your levels after a drive as the air works it's way out of the system...

Thing is... Some of these newer engines can remain air locked in some parts of the cooling system for a very long time...and that is the hazard.

Sorry, I totally missed your post talking about just that. :$

 

[Howard]

I mentioned it... no bites. It is also one of the reasons you need to check your levels after a drive as the air works it's way out of the system...

Thing is... Some of these newer engines can remain air locked in some parts of the cooling system for a very long time...and that is the hazard.

If the water pump is primed, it should be able to pump coolant to wherever it normally goes, correct? And if there is air downstream, well, it should be even easier to pump it downstream.

I'm not saying all the air will get bled immediately but I find it difficult to imagine that a cooling system couldn't circulate well enough to move air out of the way.

 

[Zargon]

It is more about the minerals on the metals than cooling capacity.

eh, like I said, if it doesnt damage anything after 100k+ miles, I am not too worried

with how often I mess with the coolant on my bikes I would go broke if I bothered to use distilled water all the time.

I would guess not ever changing the coolant is far worse than using some tap water atleast

 

[Howard]

with how often I mess with the coolant on my bikes I would go broke if I bothered to use distilled water all the time.

I get it for free.

 

[kornphlake]

There is a ton of waste water and none of it should be allowed to go into the ground. I believe in all places in the US you can just flush coolant in a toilet or household drain (not storm drain)...water treatment removes it.

This is not the case where I live, dumping anything but waste water in the sewer is a big no-no, there are several places in the city where I can drop off used coolant for recycling at no cost. Before you go and flush your coolant make sure and check with the local authorities. I dumped some diluted anti-freeze on my lawn a couple years ago, I thought that rain water and irrigation would have quickly diluted the anti-freeze to a safe level. It took almost a year for the grass to start growing in that patch again, I've been much more careful handling anti-freeze after seeing the effects. I imagine dumping anti-freeze in the toilet could damage the bacteria used for processing sewage as well as any other organisms that may come in contact with the waste water after it is treated if the sewage treatment plant isn't specifically removing the anti-freeze. I didn't search far and wide, but after spending about 5 minutes with google I wasn't able to find any credible recommendation to flush coolant, I did however find several seemingly credible recommendations not to flush it.