Coolant flushing

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Anyone tried this, my neighbor told me he's done his coolant flushing 1. Drain the radiator then plug it 2. Disconnects upper radiator hose and points it downward to a catch pan/bucket 3. Puts running water hose in radiator top filler but he doesn't "seal" it to create any kind of pressure just wants full, free flowing water going into the radiator 4. On a cold engine he turns the engine over/on for a few seconds to allow the water pump to push out all the old coolant. He says the engine will never approach anything dangerously hot as it just runs for a few seconds, long enough to pump out all the old fluid. He then does his chemical flush with only clean water being in the engine. The reason he says he does it this way is any residual coolant left in the system will retard the cleaners in the chemical flush. I asked him what about the heater core, he said he flushes that out with a final distilled water flush after the chemical clean just prior to adding his premix and doesn't worry about flushing the heater core with a chemical flush because if the chemical flush creates a leak in the heater core, it's expensive/time consuming to replace it. He said he would only ever run a chemical flush through the heater core if he saw that his cabin heat was no longer getting as hot. Any thoughts? Unless I'm missing something, and it's very possible I am, it seems like a legit method.
 
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Fwiw, I've used a method similar to this to flush the power steering system. Takes 2 people but you use the pump to flush out the old fluid while you're adding new fluid and you do it until the fluid coming out of the return line is nice bright red. (one person is in the cabin turning the wheels while another keeps clean PSF/trans fluid flowing into the reservoir as the pump sucks it up... works nicely, cleaner and way faster a better than using a turkey baster)
 
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I use a T to flush the cooling system. I drain the coolant from the bottom drain plug on the radiator, then install the T, open the heater valve, run the engine letting it shoot out the top of the radiator using a plastic elbow. After the water warms and the thermostat opens, I remove the T, connect the hose, and fill with the required straight coolant per the system capacity, too with water, run the engine until the air purges and the thermostats opens, fill with water. The reservoir gets 50/50.
 

Kestas

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I use the same method as the OP, except I remove the thermostat. I don't know how you can flush with the thermostat in there. The OP wasn't clear on one point. I remove the upper radiator hose at the radiator and aim the garden hose into the radiator hose toward the engine for a reverse flush.
 
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Originally Posted by Kestas
I use the same method as the OP, except I remove the thermostat. I don't know how you can flush with the thermostat in there. The OP wasn't clear on one point. I remove the upper radiator hose at the radiator and aim the garden hose into the radiator hose toward the engine for a reverse flush.
He's an old timer, probably in his mid 70's, maybe pushing 80. I'm almost 50 and he's a good 20yrs older than me and his cars an old GM of some kind - not sure of the year. Heck, I'm not sure he even drives any more. Maybe he doesn't have a thermostat or he took it out. I got a cousin in AZ that runs without the thermostat. He still runs a 50/50 mix but it rarely ever gets to freezing where he's at so he says he has no worries. I don't know, I think I'd be too scared to run without a thermostat but I've already lived in the NW where it freezes in the winter...he says it's quite common in lower latitudes. I just had never heard of it...
 
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Originally Posted by atikovi
Is this a car from the 50's or 60's? Unless he removes the thermostat there won't be flow throughout the entire system.
I am about to do a flush. He's my old neighbor who saw me in my driveway with the coolant and water coming from Wally's. We started shooting the [censored] and I said I was planning on replacing the thermostat since I was flushing. It's possible i misunderstood him and he was saying I should flush it out like that since I was taking the T stat out. Sometimes it's hard to understand him because of his accent, he's an old Armenian guy. Super nice, super friendly but sometimes I just ain't got a clue what he's saying....‚
 
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Originally Posted by Kestas
I use the same method as the OP, except I remove the thermostat. I don't know how you can flush with the thermostat in there. The OP wasn't clear on one point. I remove the upper radiator hose at the radiator and aim the garden hose into the radiator hose toward the engine for a reverse flush.
I never thought of doing that. You just keep pushing water in until it runs clear, yes? I've always did the drain, fill, drain, fill wash rinse repeat method to get everything out before refilling with premix. It's a pain.
 
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Originally Posted by JLawrence08648
I use a T to flush the cooling system. I drain the coolant from the bottom drain plug on the radiator, then install the T, open the heater valve, run the engine letting it shoot out the top of the radiator using a plastic elbow. After the water warms and the thermostat opens, I remove the T, connect the hose, and fill with the required straight coolant per the system capacity, too with water, run the engine until the air purges and the thermostats opens, fill with water. The reservoir gets 50/50.
That sounds similar to what I thought I was hearing. I concede that I may have misunderstood what I was being told. So you put in a tee, hook up the hose, run the water, let spill out the top of the radiator over a catch of some kind and let both the engine and water run until the water coming out the top of the radiator is clear, yes??
 
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Originally Posted by Mad_Hatter
I've always did the drain, fill, drain, fill wash rinse repeat method to get everything out before refilling with premix. It's a pain.
That is still the best and simplest way if you don't want to start taking things apart. Depending how much fluid the radiator drain plug lets out or if the block has a drain plug you can remove, it might take five cycles to get 95% of the old coolant out. And you have to drive it long enough during each cycle to get the thermostat open. And don't waste money with premix unless it's a Honda. Your last cycle is close enough to pure water anyway.
 
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Originally Posted by Mad_Hatter
Any thoughts? Unless I'm missing something, and it's very possible I am, it seems like a legit method.
A legit kit is $5.49 @ Walmart. [Linked Image] You can also: Drain radiator. Remove upper radiator hose and thermostat. Replace thermostat housing. Attach longer generic hose of correct diameter and route that to a large container. I saw one guy use a length of old fire hose. You can buy flexible generic radiator hoses without bends in just about any size. Or try to route your old radiator hose to point down towards a large container like a 5 gallon bucket. Insert water hose to upper radiator inlet. Run engine, with heater on to maximum, as clean water enters radiator, flows to engine from lower hose, as everything exits from upper hose to container. You really don't want this stuff to just run off into a storm drain, polluting the environment. When water runs clear, turn off engine. Install new thermostat, hoses (upper & lower) with new hose clamps, and drive belts (since you're at it). Add concentrated coolant to proper mix with water left in engine block. Or: Remove thermostat. Drain radiator. Refill with distilled water. Run engine. Then repeat drain & fill until you have clean distilled water only. Drain. Refill with antifreeze concentrate until desired mix is achieved. Or watch online videos:
 
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Originally Posted by atikovi
Originally Posted by Mad_Hatter
I've always did the drain, fill, drain, fill wash rinse repeat method to get everything out before refilling with premix. It's a pain.
That is still the best and simplest way if you don't want to start taking things apart. Depending how much fluid the radiator drain plug lets out or if the block has a drain plug you can remove, it might take five cycles to get 95% of the old coolant out. And you have to drive it long enough during each cycle to get the thermostat open. And don't waste money with premix unless it's a Honda. Your last cycle is close enough to pure water anyway.
Good advice. I tried to once get my block drain plug opened but that darn thing wouldn't budge and I was afraid of rounding it off or worse yet, not being able to get it back in for some odd reason. That's why I've never bothered with it. And yes, it's usually takes about 4 flushes with just water before it runs [pretty] clear. I don't think I've ever gotten the block water to run crystal clear but I like the tee method, that seems to be the best way to 100% flush out any old coolant and/or chemical flush. I'm going to look into that.
 
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Originally Posted by NormanBuntz
Okay, unless you own or work at an auto shop, what does everyone do with their used coolant?
For some strange reason none of the auto parts stores around me take coolant, oil yes, but coolant no. Fortunately I have curbside recycling and they will take coolant in a clear plastic jug but only a couple gallons at a time. So for my 10.2qt system it takes a couple weeks of putting it out to get rid of it all. Even though I've done it this way before I'm always afraid some kids will come along and dump it out where animals can get to it or worse yet, somehow the stupid kids get it on themselves playing with the stuff. It's never happened but it's always been in the back of my mind as a worry. Other than that, my locality has a waste transfer facility that will take it for free.. it's just a bit of a drive to get out there. But they'll take however much coolant you have, so you could bring in 20qts if you had to.
 
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Originally Posted by OnTheRocks
Originally Posted by Mad_Hatter
Any thoughts? Unless I'm missing something, and it's very possible I am, it seems like a legit method.
A legit kit is $5.49 @ Walmart. [Linked Image] You can also: Drain radiator. Remove upper radiator hose and thermostat. Replace thermostat housing. Attach longer generic hose of correct diameter and route that to a large container. I saw one guy use a length of old fire hose. You can buy flexible generic radiator hoses without bends in just about any size. Or try to route your old radiator hose to point down towards a large container like a 5 gallon bucket. Insert water hose to upper radiator inlet. Run engine, with heater on to maximum, as clean water enters radiator, flows to engine from lower hose, as everything exits from upper hose to container. You really don't want this stuff to just run off into a storm drain, polluting the environment. When water runs clear, turn off engine. Install new thermostat, hoses (upper & lower) with new hose clamps, and drive belts (since you're at it). Add concentrated coolant to proper mix with water left in engine block. Or: Remove thermostat. Drain radiator. Refill with distilled water. Run engine. Then repeat drain & fill until you have clean distilled water only. Drain. Refill with antifreeze concentrate until desired mix is achieved. Or watch online videos:
This approach along with using the tee, will sure beat having to drain the radiator each time for 4 or 5 times and I see it producing better results, faster and as far as insuring that you've done a 100% flush... especially since I'm unable to open my block drain plug. And the use of a generic, longer radiator hose will limit the potential of the flushing water/coolant from the block getting onto any painted surfaces or belts. That was a problem I had with just letting the relatively short (for my vehicle) upper radiator hose just spit out fluid. Even though my neighbor suggested pointing it down, I had visions in my head of fluid running all over my fans and everything else around there.
 
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Originally Posted by NormanBuntz
Okay, unless you own or work at an auto shop, what does everyone do with their used coolant?
My local waste management facility accepts Haz-Mat. Paint. Spray cans. Automotive fluid. Just drive up, and drop off.
 
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Originally Posted by Mad_Hatter
along with using the tee, will sure beat having to drain the radiator each time for 4 or 5 times and I see it producing better results, faster and as far as insuring that you've done a 100% flush...
That Prestone kit is an option. A lot of people like it. I don't. I don't like cutting into lines like that. It just creates another point for a leak down the line.
Originally Posted by Mad_Hatter
I had visions in my head of fluid running all over my fans and everything else around there.
Yes. That is exactly what happens. And then the fan is spraying all of that coolant around too. Not the kind of mess you want to make.
 
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Originally Posted by OnTheRocks
That Prestone kit is an option. A lot of people like it. I don't. I don't like cutting into lines like that. It just creates another point for a leak down the line.
Yes, I do agree. While I believe it would cut down on the time and provide better flush results, I'm going back and forth on whether or not to incorporate the tee into the process. I just hate the idea of cutting into a perfectly good hose that is giving me no issues what so ever. I'm one of those people who has bad luck (I think I broke a mirror as a kid, lol) and I can just see that tee springing a leak on me during my first summer road trip.
 
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