Write-Up: Flushing Radiator Coolant

Just about 2 gallons in my experience. One gallon of anti-freeze and one gallon of water.
I pre-mix the two or you can buy the Anti-Freeze already pre-mixed at the auto parts store. Just look for 50/50 on the bottle.
Then you just have to put it in and not be concerned with mixing it.

Rickw wrote:

Looks like the weather was nice there today for working on the car.
It's been snowing and raining and snowing here all day. And it's only the middle of October !!!!!!

Things are weird out here on the left coast, too... Last week we got 6 inches of rain in 1 day, and this morning the "few showers" that were forecast dropped 1.5 inches in 2 HOURS! In SF, water was gushing out of manhole covers.

Rickw wrote:

I pre-mix the two or you can buy the Anti-Freeze already pre-mixed at the auto parts store. Just look for 50/50 on the bottle.
Then you just have to put it in and not be concerned with mixing it.

Rick makes a good point. If you don't buy pre-mixed, or pre-mix it yourself, you'll inevitably find yourself with either too much or not enough anti-freeze in, when the system stops accepting any more...

When I flushed the hell out of my car to convert it back to trustworthy green coolant, I'm pretty sure it took more than two gallons (it's rated for 3.) However, being a cheapskate, I figured the cheap and fairly easy thing to do is this:

Buy 2 gallons of the regular full-strength anti-freeze and 2 gallons of distilled water;
Start the engine and pour one gallon of anti-freeze and one gallon of water into the empty radiator;
If the car won't accept any more when the thermostat opens, you can return the second anti-freeze - otherwise,
Pour half of the 2nd water bottle into the empty coolant jug and then top it off from the 2nd anti-freeze bottle;
Pour the rest of the water into the 2nd anti-freeze bottle, and now you've got 2 gallons of pre-mixed, 1 more for the radiator and one for topping up later.

I know it sounds a little Die Hard 3/Simon Sez, but you'll have spent (at the minimum prices) only $20 for 4 gallons of mix, instead of $30 for 3 gallons of pre-mix... Who doesn't like half price?

[quote="95 super3800"]theres a lot of muck getting built up on the inside of my coolant resevior.[/quotewhen you have the cooltaint out of the system then take the resevior(remove the litle tube what goes to the radiator and some nuts)

when you have it off but a bit of SAND in it and somekind cleaning fluid like dich waching fluid (i'm not kiding...) and add some water in it till its 1/3 full.
then but the cap on the resevior and hold one finger on the place where the tube connects the resevior and SHAKE IT!...the sand will start to rube and hit the dirt off the walls and the cleaning fluid dos not let it get stuck again...do it so long till its clean...fluch it whit water....

I cleaned mine this way

Actually, that does sound like a good way to clean the inside of those tanks

What's wrong with running straight anti-freeze? A 50/50 mix doesn't sound like it would be good for below zero temps.

I've heard straight antifreeze actually freezes sooner than a 50/50 mix! And without water I doubt it cools as well. Costs more than water, too.

Jack the R wrote:

What's wrong with running straight anti-freeze? A 50/50 mix doesn't sound like it would be good for below zero temps.

Jack,
Anti Freeze is good for corrosion protection, and to prevent freeze up. A/F actually does not transfers heat as well as water. The more A/F you use, the less heat transfer there is. That is why they tell you on the back of the container not to use more than 70% A/F to water. My neighbor actually had a chronic overheating problem that he could not figure out until he said to me "I don't understand it, I'm using 100% A/F". We drained half out, and added water. That did it. If you live in a warmer climate where there is no danger of freeze up, you are actually better off with 100% distilled water, and a bottle of Red Line water wetter or similar additive for corrosion protection. The water wetter lowers the surface tension of the water. It enhances heat transfer even more. That is what the Racers use. The engine runs cooler.

AA wrote:

I've heard straight antifreeze actually freezes sooner than a 50/50 mix!

I don't think so. I'm pretty sure I've got straight anti-freeze in the Charger (not currently running, so no overheating worries), and it floats all the balls on the temperature tester (shows what temp your mix is good for).

When using a mix I've always found it difficult to get enough of the balls to float as is sometimes necessary. Drain a little, add antifreeze, drain a little, add antifreeze, drain a little, add antifreeze. . .

Forget the floating balls.
Read the manufactures recommendations on proper mixture of anti-freeze and H2O.
50/50 provides the highest boiling point and the lowest freezing temp.

A 50/50 mix protects down to -34* How much more do you need?

http://www.justanswer.com/questions/gxu3-undiluted-antifreeze-freeze

If you dig around, some sources show that using straight antifreeze (or less than 30% water) lets the coolant freeze (or gel) easier than using a mix.



Both the green stuff and orange Dexron III coolant are ethylene glycol type antifreeze.

From Larry's link:

"As the name implies the third main function of antifreeze is to protect the cooling system from freezing. The way to achieve maximum freeze protection differs between ethylene and propylene glycol. For ethylene glycol the maximum protection is at 67% ethylene glycol in water. A ethylene glycol solution of this concentration will freeze at -84° F (pure ethylene glycol freezes at 8° F)."

There are numerous opinions about what anti freeze should be used to replace the antifreeze in your 95-99 Riviera.
Below is a link to a thread that contains many of those opinions and a great amount of information regarding Dex cool and the traditional "green" antifreeze as well as the "mixes with anything" antifreeze that is also available:

https://rivperformance.editboard.com/care-maintenance-f8/gm-dexcool-coolant-antifreeze-t1364.htm?highlight=dexcool

Personally I buy the Dex cool concentrate and mix 50/50 with distilled water and use this mixture in our 99 Riviera.

Bert

When I have used a chemical cleaner when flushing, after I drain it out of the car I like to do another run with just water in the system to be sure I have it sufficiently rinsed out and neutralized.
I always get more gunk with that second run.

Then after I drain that, I add my fresh new coolant.

I also mix the coolant closer to maybe 60 or 70% since there will still be a certain amount of plain water in the block yet.
I figure once it all gets mixed together in the engine I am then closer to a 50% mix.

AA wrote:

Both the green stuff and orange Dexron III coolant are ethylene glycol type antifreeze.

I was under the impression that DexCool (Orange) was Propylene Glycol, which is the supposed culprit in the LIM gasket failure.
Or am I incorrect on this.???? I guess I need to do some research as I can't remember anymore.
I used to know.....Duh.....Getting old SUCKS.
Can't remember shit.

Nope, I think Propylene Glycol is the new stuff that's said to be less toxic than normal antifreeze. DexCool is Ethylene Glycol as far as I know.

Links:

http://www.getahelmet.com/jeeps/maint/dexcool/

http://chevelles.com/forums/showthread.php?t=64731

http://www.automotiveforums.com/t941573-dex_cool_and_malibus.html

Rickw wrote:

AA wrote:

Both the green stuff and orange Dexron III coolant are ethylene glycol type antifreeze.

I was under the impression that DexCool (Orange) was Propylene Glycol, which is the supposed culprit in the LIM gasket failure.
.

You're right, everything after 35 is straight downhill! Thank God for the internet, so I can re-learn everything I've forgotten...

The bad stuff in Dex-Cool is OAT, organic acid technology, which replaced the 'green' silicates. Besides long life, it was also supposed to be better for aluminum engines, at least until the green stuff got reformulated yet again. If I had a Northstar or a Shortstar, I'd probably use it. But since our engines are good ol' cast iron, and I hate changing gaskets, water pumps, etc, I converted to green upon the recommendation of my brother, who's been doing it for a lot of his customers at the shop...

This is a good page, and there is a good OAT link in the 3rd paragraph - HOAT is also mentioned, the Hybrid "mixes with anything" stuff. Be sure to click on the Ford "anti-OAT" sticker at the lower left corner of the page:

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

I just did a radiator flush, surprisingly the tank and coolant itself had very little crud in it and when testing the old coolant, it rated almost as high as the new coolant I put in it in terms of hot and cold protection.

On a side not: I was tightening the radiator drain bung before filling the system and I thought I stripped it. I tightened a few too many turns and then it skipped. I took it out and inspected the plug and rad threads but didn't see any damage. I re-tightend and it squeezed down well, stopping one turn sooner then I did the last time. I ran the car for a while to top it up and didn't see a leak. Is it possible that it didn't strip because its plastic ?

Eldo wrote:

But since our engines are good ol' cast iron, and I hate changing gaskets, water pumps, etc, I converted to green upon the recommendation of my brother, who's been doing it for a lot of his customers at the shop...

What do you mean Eldo? because I was told that changing the coolant every five years with Dex-Cool would extend the life of the water pump?

The concern with Dex-Cool (orange) is that it deteriorates the lower intake manifold gaskets prematurely.
Some have had problems, others have not.
If the system is clean and all air (oxygen) is purged out then it appears to be safe.
From what I've read is that too much air or oxygen in the system will cause the Dex-Cool to become acidic or corrosive to certain types of gaskets. I don't know for sure on any of this data as there are more write ups in so many different places regarding Dex-Cool and it's ability to ruin gaskets that i don't know what is fact or fiction any more.
With all that said the regular Ethelyn Glycol (green stuff) can be used to replace the orange stuff if you have flushed the system completely and no orange remains, then use green coolant from then on and you won't have to worry about what Dex-Cool does to intake manifold gaskets.
Regarding the plastic drain plug, I think I did the same thing a couple of flushes ago and after removing the plug and inspecting it and finding no problem I re-installed as you did with no leaks or drips since then.
I would just keep an eye on it for a little while and if no drips then forget about it.

The main concerns about Dex-Cool are gaskets, plastic manifolds and gunk buildup. I added water pump just because the first new pump I put on my car lasted but 5,000 miles...

The link I included has more in-depth info, as well as some great pictures of orange gunk.

My car has almost 240,000km on it and I've never seen stuff like in those pics. Interesting link though Mark, its kinda scary. My fear now is that I bled the system OK, if the culprit is indeed air. I opened the bleeder screw on top of the the thermastat housing. I didn't see spitting, but rather a trickle, perhaps I didn't have it opened enough. I guess i will be checking out the tank now and then for any build up!

Thanks for the re-assurance on the overtightening Rick .

Let it warm up and try bleeding it again. Let fluid run out of the little hole for a while. It can't hurt.

One thing that would be easy to overlook or to not notice when servicing the radiator is to be sure and verify that the drain pipe inside the radiator overflow reservoir and the hose that goes from the reservoir to the radiator are not clogged. That little metal tube inside the overflow reservoir is easily clogged and it only takes a few minutes to remove and clean the reservoir. While you have it off check the hose to make sure its not clogged.

Bert

Bert makes a good point about the overflow tank system... That is what keeps the system "air-free".

As far as bleeding, I'm old-fashioned. Even sitting on flat ground, I don't think that in our chassis's the thermostat housing is the high point of the system. My memory's weak, but I think it WAS in the LeSabre/Park Ave bodies. Even if there's any doubt, I would just park the car pointing uphill, and let the air out the filler neck, while topping it off with coolant mix...

I recently tore down my 140K engine which has had dexcool 100% of the time. I thought the plastic LIM gaskets were _slightly_ warped, but not bad and certainly not leaking. I drain and refill my radiator with fresh coolant every year. (not a full system flush)

It takes about a gallon, and that way the contents don't become overly acidic or whatever.

I suppose I could do exactly the same procedure with the green stuff and I'd never have any problems with that either, so there's really no benefit to using one over the other.