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radiator flush

pronigierpronigier Member Posts: 19
Most shops seem to do a drain and fill, even the dealer. One independant said with confidence " yes sir on that car its a drain and fill" Like a Toyota has unique ability to clean it own coolant while you drive. How do they get away with that ? I have even heard that some shops will put a chemical in and then just do a drain and fill. Leaving most of the chemical still in the system. They might charge 69 dollars for changing the coolant but all they do is drain and fill. Drain and fill is easier than an oil change I would have done it myself if all they were going to do drain the radiator.


  • Mr_ShiftrightMr_Shiftright Sonoma, CaliforniaMember Posts: 64,482
    Well the idea is to remove sediment and refresh the coolant. It's not supposed to unclog a clogged radiator. If your radiator is clogged, you are beyond "a flush". It's time to pull it and clean it. So drain and fill is a preventative meassure, like an oil change.

    The only reason you might not want to do it yourself is that coolant is messy, dangerous to animals if spilled, and it's a hassle to dispose of (in California, you cannot throw it in a dumpster ). And sometimes it's HOT, too.

    But if you're willing to endure all this to save $50, more power to you!
  • joe3891joe3891 Member Posts: 759
    The proper way to replace coolant is to drain & flush several times with plain water, because all the old coolant will not drain out, even if you pull the block drains, which you should.
  • q45manq45man Member Posts: 416
    Your car comes from the factory with deionized or distilled water, using tap water to dilute AF is risky just because you can drink it don't think it's good enough for cars!.....less than 1 in 100 dealers use distilled water for flushes or fills....customers won't pay and it adds to much life to components.
  • spokanespokane Member Posts: 514
    Q45man, I agree that demineralized water in the coolant is much better than the city water in many areas but had not heard the recommendation than flushing be done with it. Since flushing can (and should) use quite a bit of water, and does not remain in the system long enough to react, don't you consider city water generally suitable for flushing even though a small amount of it will remain in the system? Too, haven't you found demineralized water to be preferable to distilled water?

    Separately, I have seen a number of write-ups, even in Popular Mechanics, that don't make reference to the block drain. I agree with joe3891 that the block and radiator drains should both be used but, apparently, many folks don't seem to agree.

    Disposal of used coolant is a serious issue but waste-water treatment engineers have pointed out that modest amounts of ethylene glycol will enhance the biological treatment process. Accordingly, some municipalities do specifically allow (or even encourage) sewering of this material. Be careful, of course, some may also disallow it.
  • jlflemmonsjlflemmons Member Posts: 2,242
    On my Safari van with rear heater, I got underneath and first drained the radiator and refilled with "soft" water. For those of you who don't live in central Texas with its super high calcium carbonate (read: disolved limestone)water, most of us have water softeners on our house plumbing. Then I removed the feed and return lines to the rear heater core. I put a hose from the softener to the return side and a hose to the sewer cleanout on the feed side. Ran the van for about 30 minutes with the water flowing through everything but the rear heater core, which was drained. Lots of crud came out of the hose even though the system had been drained and filled regularly. When the line to the sewer flowed clear for several minutes, I shut down the water, drained off about two gallons and added antifreeze to bring the total up to a 50/50 mix. That should do it!
  • joe3891joe3891 Member Posts: 759
    GM states that if the water is good enough to drink its good to mix with coolant,its worked for me since 1956.
  • sdayalanisdayalani Member Posts: 60
    havoline manufactures extended life coolants that are premixed with 50% water. that should take the guesswork out of what kind of water to use (or not use).
  • joe3891joe3891 Member Posts: 759
    Mixed costs too much.
  • gslevegsleve Member Posts: 183
    buy distilled water and mix you'll be fine
  • spokanespokane Member Posts: 514
    Joe, since 1956? That's a long time; you should be about ready for a coolant replacement.

    Sorry, I couldn't resist. I, too, have normally used drinking water for 40+ years and had no significant problems. GM's Harrison radiators, however, seem to have a life of about eight years but it's my impression this is independent of the water chemistry.
  • q45manq45man Member Posts: 416
    The factory fill of every manufacturer is deionized [no dissolved solids, no chemicals] water. Commonly made by distillation or ionic filters.
    Each engine may be different [iron block, aluminum heads, all aluminum, all iron, different alloys of aluminum, different radiator alloys,different water pumps, thermostat metals, etc].
    Making a single formula of AF work under all circumstances is a big compromise in that you have things not needed for one and maybe not enough of some additive for another type of metal.
    Additive for iron really get in the way in all aluminum engines!
    In a perfect world you would mix pure Ethylene Glycol with pure water and select from a 8-16 ounce additive package to complement and protect your individual most SemiEngines whose radiators last 500,000 miles.
    You would test the solution once-twice a year and add a suplemental amount of additive to corrrect for depletion.

    If you think about it where does the crud that blocks radiators come from? From the unused additives interreacting in non normal ways, the glycol turns acidic and attacks the interior of radiator and moves metal to the colder bottom of radiator helped by gravity....the blocking pile builds from the bottom.
    Most common brands work ok for a while but draining the sludge build up and changing the additives is important because the new long life formula may contain 2-3 times [%] the volume of additives thus if something goes wrong there can be 2-3 times the build up in radiators.

    Many consider my annual change while using [150k] long life AF excessive even wasteful, but it is just a part of my planned total maintenance.
  • joe3891joe3891 Member Posts: 759
    We think the same because we grew up in the same era.The radiators now are alumium,plastic with gaskets, no wonder.

    q45man If it makes you feel good i won't fault it.Some pay $4.00 to $5.00 for a quart of oil and change every 3000 mi.
  • Mr_ShiftrightMr_Shiftright Sonoma, CaliforniaMember Posts: 64,482
    Yep, that's what I do, and foolish or no (who can say for sure?) I've never lost an engine on any car I've owned. Maybe I do overspend on maintenance, but I definitely underspend on repairs. I've had terrific luck with all my vehicles.
  • q45manq45man Member Posts: 416
    After dealing with thousands of Ultra Premium cars [Lexus, Infiniti, BMW], my analysis of the radiator situation lead me to have Griffen [they build all the NASCAR units] construct a special all aluminum [double thick] radiator for my car......the radiator will out live me and I'm only 53.
    To protect it I flush and refill every year.

    The bulk of the aftermarket and a few dealers purchase look alike non factory units which cool 20% worse than OEM [fewer fins per inch], they weigh less [thinner aluminum, thinner plastic] but they cost 1/4 of OEM so the customer is happy for a while!
  • joe3891joe3891 Member Posts: 759
    I have learned in my long life that peace of mind costs money,lots of it.
  • Mr_ShiftrightMr_Shiftright Sonoma, CaliforniaMember Posts: 64,482
    Yep, and you never quite get there, do you...LOL!
  • joe3891joe3891 Member Posts: 759
    You just have to move on.
  • jgmilbergjgmilberg Member Posts: 872
    I remember seeing a radiator cap with a sacrificial anode attached with a brass chain. It was supposed to keep the acid from attacking the radiator core. I don't know if it was a gimmick or not. I never used one. I can't find anything about them on the net, but I know I saw them before.
  • q45manq45man Member Posts: 416
    Q45 have a special pipe [rad, rubber hose, Anode PIPE bolted to block, rubber hose, engine block] designed to corrode under stress [acidic coolant].
    If the PH never gets below 7.0 [neutral] electrodynamic corrosion doesn't occur in water [except sea water high salt].
    Simple to test with VOM for parasitic voltage generation lead on aluminum rad, one lead in solution middle of filler neck any voltage measured a no no! nothing above 10-20 millivolts.
  • sdayalanisdayalani Member Posts: 60
    due for a change.
    is it ok to use the extended life antifreeze on a 99 mazda protege 1.8L instead of the regular one?

    the extended life af/c conforms to GM's DEXCOOL specs. i was wondering if i could use it in my protege without any adverse effects. (i dont plan to go 5 yrs/250K miles though). i like the fact that it extends water pump life and its not much costlier than the normal af/c.

    has anyone ever done this before? tks
  • joe3891joe3891 Member Posts: 759
    I would look in the owners manual and use what the manufacture recommends.
  • swschradswschrad Member Posts: 2,171
    there have been a number of posts as well about DexCool turning into DexCementBlocks in a number of GMs. nobody has any real answers on how to stop it. nothing like a big chunk of solid orange crud to say, "your lifetime coolant is done, because your car's lifetime is over."

    I don't trust "lifetime" anything. that's another way of somebody else telling you to shut up and roll over, you're dead when I tell you.
  • sdayalanisdayalani Member Posts: 60
    mazda recommends an ethylene glycol-based coolant.
    now the extended life af/c by havoline (yes, the orange stuff) is also ethylene glycol-based.

    i just dont know whether the absence of borates/nitrates etc would have an adverse effect on my car's cooling system.

    nevertheless, irrespective of what coolant i use, i plan to change it every 30 months/48,000km as per mfr recommendations
  • dudleyrdudleyr Member Posts: 3,469
    What would be the best coolant to use for a Honda. I have two that need their coolant changed. I have heard the Honda mechanics say that Honda brand should be used (it looks absolutely brand new even after 4-5 years), and would buy that except the nearest dealer is about 200 miles away. Would regular old Prestone be just as good?
  • spokanespokane Member Posts: 514
    You are correct that Honda says to use their coolant but a very reputable dealership in my area used Texaco for years until someone in the organization requested a change to the house brand. The Texaco worked fine. I wouldn't use the GM orange stuff. I have used Prestone in one Honda for 125,000+ miles and the cooling system is in excellent shape. However, don't ignore the Honda voice entirely; you really do need to use their power steering fluid.
  • joe3891joe3891 Member Posts: 759
    I have read all the posts on the dex-cool sludge and there must be something to it.I now have two vehicles with factory filled dex-cool one with 24000 and 19000 and have yet to see a problem,if something comes up I will post it.
  • mrdetailermrdetailer Member Posts: 1,118
    I had to replace my clogged radiator with an after market one. It is a better radiator. It's oversized and cools much better. The only complaint I have is that the thermostat is more active. It will get close to high before the thermostat opens. When it does it immediately drops to operating temp. If stressed, it can really cool fast.

    So I guess it depends on what you buy.
  • acuraowneracuraowner Member Posts: 57
    The reason Honda/Acura is really intent on having you use their coolant is because its specially formulated for the all aluminum engines in Honda/Acura vehicles.

    Now your basic Prestone may be able to claim their coolant has low silicate levels. But its not quite as low as Hondas.

    But now the silicate levels only really affect the waterpump and waterpump seals. But when Honda replaces your waterpump at every timing belt replacement its not much of an issue.
  • bburton1bburton1 Member Posts: 395
    If your water comes from your own well and you have a brine/salt type softener, never use this stuff to dilute coolant. It contains a fair amount of sodium chloride/salt and will wreck your cooling system. Buy a gallon of distilled water for less than a buck and mix them together.
  • webguysterwebguyster Member Posts: 434
    I just had 30,000 mile service done to my 00 Camry Solara, that came with the factory red coolant. When I got home, I checked the coolant and it was green. I called the service advisor, who said its the same stuff. I looked on the web for more info and the owners manual, and it says to use a specific coolant for aluminum radiators. I called another Toyota dealer that told me to get it flushed immeadiatly, so I called the service advisor back, and after waiting for about 10 minutes, he said bring it back. I am concerned that not only could I have suffered some warping from 2 drain and fills, and a flush with water, at HOT temps coming from driving, and that the residue may cause future problems, as well. Any suggestions. Not only did I waste 5 hours of my day, but I don't really believe it is required to change the Long Life RED coolant at 30k. Any comments?
  • 99protege99protege Member Posts: 1
    red coolant stuff. i'm only aware of green (ethylene glycol-based) and orange (extended life af/c, GM dexcool)
  • mbbenzmbbenz Member Posts: 47
    yes the Toyota long life coolant is red. I have not seen it sold anywhere else than the dealers. My 99 Lexus calls for the same thing. At 30k miles there is no need to flush it. At 60k I will have mine done. But I do have a gallon in my garage so that I could top up if necessary. All Toyota/Lexus dealers around here uses that so I don't know what brand they used for your car thats green. It costs me $13.99 for the gallon but you can browse the web there are some Toyota dealers selling for $9.99 and I believe they can ship to you as well. You probably didn't do any damage running the green stuff anyways.
  • adc100adc100 Member Posts: 1,521
    My understanding is that it was invented to prevent the dreaded intake manifold gasket leaks on the GM aluminum head sixes. I personally have had 2 3.1 V 6's and both required the heads to be replaced. They were earlier ones so ddn't come with the dex cool at the tme. I have also heard about the dex-cool having problems. It may be the lesser of two evils. Also I would never-never-never use tap water to mix with anti-freeze.
  • spokanespokane Member Posts: 514
    I cannot comment on the degree of difference between the "red" and "green" formulations but I feel sure that brief use of an alternate type has done no damage to you cooling system. IF damage could occur, it would be associated with chemical action over a period of months.
  • donlinodonlino Member Posts: 31
    Help, here are the symptoms:

    93 Legend 94,000 miles. Car starts to overheat on occassion. Engine also then begins to occasionally surge. It revs from back and forth from 1,000 rpm to 1,500 in park. No heat comes out of the air vents when engine temp begins to climb to an overheated situation. I shut the engine down before it ever hits the red zone.

    I replaced the thermostat a week ago and refilled the radiator with coolant. I bled the radiator hose from the valve on the top hose and everything was ok for a week. Then samething happens. Park the car and check a few hours later and the radiator is low. I refill and bleed again. The next day engine temp ok, heat working. After about three hours, I take the cap off of the radiator since it was not hot but cool, and there is a lot of pressure and the fluid shoots out. What is going on here? Why is this car overheating and yet no heat is produced when it does? I am at my whit's end. Any help greatly appreciated.
  • pronigierpronigier Member Posts: 19
    They did this to me also, but the first one was just a drain and fill. After it all turned brown I new what they had done abd called and they confirmed that they do just a drain and fill. So I spend 100 to get it all fluhed out. Now with the sludge and smoking , why did I bother.
  • joe3891joe3891 Member Posts: 759
    When the fluid is low you will not have heat,the high pressure is caused by bad head gasket and or cracked head,sorry.
  • spokanespokane Member Posts: 514
    As joe3891 says, donlino, it sounds like a bad head gasket. A blown gasket can allows combustion gasses to be forced into the cooling system; causing your symptoms. It can also allow coolant to leak into cylinder(s) and thus into the crankcase. Since running the engine increases the likelihood of cylinder head warpage and bearing damage from contaminated oil, I would tow it to a capable shop right away. Your focus on bleeding the cooling system was correct but once you established coolant flow through the heater core, the system was purged of almost all the trapped air.
  • ocelot1ocelot1 Member Posts: 101
    Is the texaco longlife coolant the same as the Dexcool? I thought the GM Dex was made by texaco? I think I might switch to the Toyota red,in my mitsubishi montero. Currently using the texaco longlife Orange.
  • adc100adc100 Member Posts: 1,521
    I believe that DEX-COOL was developed by Texaco in conjunctionn with GM. Allegedly to provide a lifetime coolant, but more specifically to address the problem of GM's leaking intake manifolds on their aluminum head V-6's. The DEX-COOL has been linked to turning jelly-like in the coolant system. I can't prove it personally though. I would think though that this would occur after a long period of time possibly with some other problems in the engine. If I were you I would not rush out to change until the stuff is in there for say 30K or so.
  • q45manq45man Member Posts: 416
    When incompatable coolants are mixed [not flushing out the system completely], they can react forming a gel IF left in years without changing.
    The problem is seen most often when the radiator is only drained [< 40% of total coolant].
  • gslevegsleve Member Posts: 183
    that a backflush kit usually involves a tee valve in one of the heater core hoses, then screw in a garden hose on the tee valve turn on water open radiator cap and petcock run engine 20min or 30min usually will flush the system including the heater core
  • joe3891joe3891 Member Posts: 759
    When you read cooling system capacity does it also include the amount in the overflow tank to the cold level.
  • adc100adc100 Member Posts: 1,521
    They are another weak link in your coolant system integrity. Both times I have installed them I developed a hose failure there. If you are going to use one, buy a new OEM heater hose and install it before you put on the new hose (double clamp it)
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