Coolant flush .. How many times?
07-01-2015, 09:27 AM
#1
Coolant flush .. How many times?
Simple question:
How many times do you need to flush when you drain the system through the radiator drain plug ?
It has never been done before (2006).
I've got 2 gallons Dex cool and 2 gallons distilled water for instant fill without a flush.
If I want to flush 1 time I need to buy 4 gallons distilled water (flush with only water)
flush 2 times, I need 8 gallons.. etc etc
Reason for asking that I need to know how much distilled water I need to buy.
Thanks!
How many times do you need to flush when you drain the system through the radiator drain plug ?
It has never been done before (2006).
I've got 2 gallons Dex cool and 2 gallons distilled water for instant fill without a flush.
If I want to flush 1 time I need to buy 4 gallons distilled water (flush with only water)
flush 2 times, I need 8 gallons.. etc etc
Reason for asking that I need to know how much distilled water I need to buy.
Thanks!
07-01-2015, 10:31 AM
#2
Le Mans Master
Within the last few months I just did this.
Can't recall if I made a post with comments so OP could try a search.
My recollection is it took 4 drain and refill/ flushes to attain perfectly (perfectly) clear water.
I bought 8 or 10 gallons of distilled and the left over is OK for me to keep for other uses.
Yep took 2 gallons Dexcool.
Have fun!
Can't recall if I made a post with comments so OP could try a search.
My recollection is it took 4 drain and refill/ flushes to attain perfectly (perfectly) clear water.
I bought 8 or 10 gallons of distilled and the left over is OK for me to keep for other uses.
Yep took 2 gallons Dexcool.
Have fun!
07-01-2015, 01:57 PM
#3
07-01-2015, 09:59 PM
#4
Truthfully - I wouldn't bother doing more than 1 "flush" cycle. Read that as draining the factory coolant out - filling with distilled water - running the car - draining the cooling system again and then refilling with new Dex-Cool and distilled water.
Sure - you can do it many many times, but the idea here is to get fresh coolant into the cars cooling system. The reason for that is pretty simple - while the "anti-freeze" will not lose it's ability to keep the cooling system from freezing - it will lose it's anti-corrosive properties over time. (a good way to envision it is to think of the additive package in anti-freeze as sacrificial, and over time it looss it's ability to protect). By draining the old stuff out, and putting new coolant in - you are "renewing" the additive package that's part of the anti-freeze.
IMHO - You don't need to try to get every last drop of the old coolant out - you need to get new coolant (with new anti-corrosion additive "package" in). So - if you assume that you get two thirds of the capacity of the system out when you drain it - you'll have roughly 90% of the old stuff out after the one flush. (A 2nd flush cycle will get about 95% of the old stuff out.) Put in enough new Dex-Cool to create a slightly "stronger" than 50% mix, and you should be more than good to go. Personally - I would rather drain the system and refill it every three years (as opposed to five years that the factory recommends) than go nuts with multiple flush cycles trying to get every last bit of old coolant out.
Sure - you can do it many many times, but the idea here is to get fresh coolant into the cars cooling system. The reason for that is pretty simple - while the "anti-freeze" will not lose it's ability to keep the cooling system from freezing - it will lose it's anti-corrosive properties over time. (a good way to envision it is to think of the additive package in anti-freeze as sacrificial, and over time it looss it's ability to protect). By draining the old stuff out, and putting new coolant in - you are "renewing" the additive package that's part of the anti-freeze.
IMHO - You don't need to try to get every last drop of the old coolant out - you need to get new coolant (with new anti-corrosion additive "package" in). So - if you assume that you get two thirds of the capacity of the system out when you drain it - you'll have roughly 90% of the old stuff out after the one flush. (A 2nd flush cycle will get about 95% of the old stuff out.) Put in enough new Dex-Cool to create a slightly "stronger" than 50% mix, and you should be more than good to go. Personally - I would rather drain the system and refill it every three years (as opposed to five years that the factory recommends) than go nuts with multiple flush cycles trying to get every last bit of old coolant out.
07-01-2015, 10:39 PM
#5
The best way to check the quality of your DEX is to use a multimeter. You put your negative probe to the negative post on your battery. You then place the positive probe in the neck of your radiator, making sure that the positive probe touches nothing but the antifreeze. Make sure the coolant is warm.
0.2 V to 0.5 V - antifreeze is still good
0.5 V to 0.7 V - antifreeze is borderline
0.7 V or greater - antifreeze is unacceptable.
You can also use test strips (available at a quality auto parts store for $5 or less), they work on both green and red types too. But if you already have a multimeter, why go buy test strips? The multimeter is the more technically accurate method
Low fluid level will cause sludging. There is a GM Technical Service Bulletin (TSB) on this matter. Dex-Cool's extended service intervals are made possible from its patented organic acid corrosion inhibitor system that eliminates the need for silicates, phosphates, borates, nitrites, and amines. Elimination of these additives is significant because many of them are abrasive to water-pump seals.
Another way to ensure longer life of parts and get better corrosion protection is to make sure you USE DISTILLED WATER when mixing with antifreeze. By just using regular tap water you contaminate the new Dex-Cool and drastically lower the corrosion protection.
0.2 V to 0.5 V - antifreeze is still good
0.5 V to 0.7 V - antifreeze is borderline
0.7 V or greater - antifreeze is unacceptable.
You can also use test strips (available at a quality auto parts store for $5 or less), they work on both green and red types too. But if you already have a multimeter, why go buy test strips? The multimeter is the more technically accurate method
Low fluid level will cause sludging. There is a GM Technical Service Bulletin (TSB) on this matter. Dex-Cool's extended service intervals are made possible from its patented organic acid corrosion inhibitor system that eliminates the need for silicates, phosphates, borates, nitrites, and amines. Elimination of these additives is significant because many of them are abrasive to water-pump seals.
Another way to ensure longer life of parts and get better corrosion protection is to make sure you USE DISTILLED WATER when mixing with antifreeze. By just using regular tap water you contaminate the new Dex-Cool and drastically lower the corrosion protection.
The following users liked this post:
dmk0210 (05-28-2016)
07-02-2015, 06:43 PM
#7
Burning Brakes
Dealer just did mine. They used a cleaner product ,then replaced coolant. I would have spent hours and flushing and burping the system. I don.t see the savings doing it your self.
07-03-2015, 09:00 PM
#10
2 Gallons of Dex Cool run about $30 at Wal Mart, and four gallons of distilled water run another $4. To do the drain and refill takes roughly 45 minutes - each flush adds another 30 - 45 minutes to the job. (Then you have to get rid of the old coolant - sometimes not the easiest thing to do.) So - 2 hours would get 'er done. If you have to bother friends for rides to the dealership, or hang out there and wait for the work to be done - there is time lost there as well.
I'm not going to argue the merits of doing your own work vs. having someone do it for you. There are professional mechanics that do really excellent work, and who treat their customers cars better than they treat their own. There are also some professional mechanics that cut every corner in the book, and couldn't care less about how good the work they do is as long as the car makes it out of the parking lot.
Suffice to say that you spent an additional $100 to have the dealer do the job, truthfully - in the overall scheme of things - that isn't a lot of money when you're talking the cost of a C6.
Remember to anyone looking at this post - IF you use a cooling system cleaner - then you need to do multiple flushes or remove the block drains to get all the old coolant out. You don't want any residual cleaner sitting in the system for years and years.
I'm not going to argue the merits of doing your own work vs. having someone do it for you. There are professional mechanics that do really excellent work, and who treat their customers cars better than they treat their own. There are also some professional mechanics that cut every corner in the book, and couldn't care less about how good the work they do is as long as the car makes it out of the parking lot.
Suffice to say that you spent an additional $100 to have the dealer do the job, truthfully - in the overall scheme of things - that isn't a lot of money when you're talking the cost of a C6.
Remember to anyone looking at this post - IF you use a cooling system cleaner - then you need to do multiple flushes or remove the block drains to get all the old coolant out. You don't want any residual cleaner sitting in the system for years and years.
07-05-2015, 04:27 PM
#11
Le Mans Master
Drain your radiator leave open. Start engine and pour your water into the tank until you see clear water running out of the radiator, shut down engine, close radiator then add coolant and water to 50/50 mix.
07-06-2015, 01:16 PM
#12
Team Owner
I won't argue the point, as many here disagree, but the manual says tap water, not distilled. Distilled water is aggressive...it wants to pull minerals from the system (your engine and cooling system). Tap water is not as aggressive. 
07-06-2015, 11:30 PM
#15
The best way to check the quality of your DEX is to use a multimeter. You put your negative probe to the negative post on your battery. You then place the positive probe in the neck of your radiator, making sure that the positive probe touches nothing but the antifreeze. Make sure the coolant is warm.
0.2 V to 0.5 V - antifreeze is still good
0.5 V to 0.7 V - antifreeze is borderline
0.7 V or greater - antifreeze is unacceptable.
You can also use test strips (available at a quality auto parts store for $5 or less), they work on both green and red types too. But if you already have a multimeter, why go buy test strips? The multimeter is the more technically accurate method
Low fluid level will cause sludging. There is a GM Technical Service Bulletin (TSB) on this matter. Dex-Cool's extended service intervals are made possible from its patented organic acid corrosion inhibitor system that eliminates the need for silicates, phosphates, borates, nitrites, and amines. Elimination of these additives is significant because many of them are abrasive to water-pump seals.
Another way to ensure longer life of parts and get better corrosion protection is to make sure you USE DISTILLED WATER when mixing with antifreeze. By just using regular tap water you contaminate the new Dex-Cool and drastically lower the corrosion protection.
0.2 V to 0.5 V - antifreeze is still good
0.5 V to 0.7 V - antifreeze is borderline
0.7 V or greater - antifreeze is unacceptable.
You can also use test strips (available at a quality auto parts store for $5 or less), they work on both green and red types too. But if you already have a multimeter, why go buy test strips? The multimeter is the more technically accurate method
Low fluid level will cause sludging. There is a GM Technical Service Bulletin (TSB) on this matter. Dex-Cool's extended service intervals are made possible from its patented organic acid corrosion inhibitor system that eliminates the need for silicates, phosphates, borates, nitrites, and amines. Elimination of these additives is significant because many of them are abrasive to water-pump seals.
Another way to ensure longer life of parts and get better corrosion protection is to make sure you USE DISTILLED WATER when mixing with antifreeze. By just using regular tap water you contaminate the new Dex-Cool and drastically lower the corrosion protection.