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Discussion Starter #1
I've been with this forum for awhile as well as a few others, and, one consistent issue seems to appear time and time again, and, that is flushing and filling the coolant system and people reporting engine overheating or no heat afterwards. I have stated this procedure before in followup posts and replies, however, am now making it official..... This is a standard procedure for the Equinox, however, can be followed with most closed coolant systems.

First of all, somethings to keep in mind:

- This is only 15lb. of pressure system. One of the lowest pressure coolant systems when compared to others and is also one of the fastest cooling. If you feel there is more pressure in your coolant system than 15lbs., then please have a compression check done on your vehicle's engine to check for a leaky head gasket.

- Please, please, please, please make sure that the coolant fans are working properly, both the low and high. Always make sure that at least the low fans run before even starting this procedure, for, not doing so may cause damage to the engine. If the low fans are not functional, clean the contacts on the passenger side fan.

- Burping the system should not be required and almost never works. If burping is needed, please have a compression check done on the vehicle's engine for possible leaky head gaskets.

- Do Not Remove The Coolant Bottle Cap At First. This is the biggest mistake that many make and causes air to get sucked into the system and displaces coolant.

- Do not always go by what the temp gauge says during this procedure. The reason is, before draining, it is showing the coolant still sitting in the engine's temperature and not the temp of what's in the radiator or bottle, an, by the time that gets to draining, it's already cooled down.

- Use The Orange DEX Cool Coolant (or a derivative) Only when refilling. GM sensors no longer support the boiling temperature of the green coolant, and, therefore, can result in damage to the engine if DEX Cool is not used.

- This procedure can take up to an hour and a half to 2 hours, so, please plan accordingly.

Ok, let's begin:

1. Wait for your vehicle to cool for at least 15-20 minutes if it has been running, and, then unscrew and remove the coolant spigot from the radiator usually on the lower driver's side

2. Pay attention to the drainage. When it slows to a slow drip, slowly unscrew the coolant cap on the bottle only enough to allow coolant to flow out of the system again via the spigot, but, do not remove yet.

3. Once completely drained, replace the spigot, and remove the coolant cap completely. From here, put in your favorite coolant system flushing detergent (For me, it's usually Prestone Super Flush), and, slowly refill the coolant system with cold water until full.

4. Start the engine, turn the heater on upper vents, and pay attention to the temperature gauge, fans, and temperature coming out of the vents. The air will be cold and the temp gauge will reach operating temperature and sit there for 5-8 minutes. This is normal.

5. After this time, you will notice the temperature start to rise slowly, the coolant fans go from low to high, yet, the air in the vent will remain cold. The temperature will get up to just below the red mark, but, never directly on it for roughly 5-8 minutes. This is normal. The reason is that the water on one side of the thermostat is cold, while the water on the other side is hot, and, must heat the thermostat to opening temperature. This also is an indication that the thermostat is working correctly.

6. Once the thermostat opens, you'll notice a brief water rush sound behind the dash/heater core, and, you'll notice the temperature gauge start to drop, and the vents start to warm up. Once cooled to operating temperature, wait at least 5-8 minutes before shutting off the engine and completing the "Wash Cycle."

7. (The Rinse Cycle) Repeat steps 1 and 2, then, once completely drained, replace the spigot, and remove the coolant cap completely. From here, simply refill the coolant system slowly with cold water only. For heavily soiled systems, you may repeat step 3 a well if you feel it needs a second wash cycle.

8. Repeat steps 4 through 6. Once the first rinse cycle is complete, repeat it at least once more. If you did a second wash cycle, then repeat the rinse cycle once again.

9. (Coolant Charge Cycle) Once complete, repeat steps 1 and 2, then, replace with your favorite GM DEX Cool Coolant (up to 2 bottles) and water, or a 50/50 mix (usually around 2 to 3 bottles). Repeat Steps 4 through 6. Once these steps have completed, allow the engine to cool at least once more for 15 to 20 minutes, then, slowly open the coolant bottle cap, and fill the bottle to the top if necessary and start the engine. Do not worry about over filling. if it is over filled, the coolant will simply boil out the overflow tube on a healthy system. Verify that the heat rises to as warm or hot as it was before, and the temperature gauge remains at normal operating temperature.


This concludes the proper flush and fill coolant exchange procedure for the Equinox and several other closed coolant systems.

I hope this helps many of you.

Starflare5.
 

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Pushback on use of chemical flush and draining the radiator via the petcock/spigot in 5 ... 4 ... 3 ... 2 ....
 
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Discussion Starter #4 (Edited)
To explain: The Prestone Superflush is the safest to use, and, you cannot possibly flush the system well when it is that old without a detergent flush. Plus, even GM has their own detergent flush now that is practically the same thing......

It's called AC Delco Fast Flush - GM Part Number: 89021562

Replaced by Prestone Super Flush - GM Part Number: 88864026

Note: Most of us that have first Gens, they have been used and abused by previous owners. Heck, my newly obtained 2LT was from Arizona, and, I kid you not, literally had mud in the coolant system.. In addition, the bottle was so dark, you could not see the coolant level (and had to be replaced due to cracking).
 

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What’s the concern with using a chemical flush? Damage to the water pump, thermostat, radiator, heater core, or temperature sensor? Or is it dislodging and relocating crud that could create a blockage somewhere else where it could ultimately cause engine damage? Or is it fear that you’d never get all the chemical out?
 
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Dude! This is Awesome Information. Thanks For Taking Your Time to Post This. This is "Exactly" Why I Joined This Site. Kudos to You. Good Karma is Coming Your Way For Such a Great Act of Concern For "All" of Us. Thanks Again.
 

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Discussion Starter #7
What’s the concern with using a chemical flush? Damage to the water pump, thermostat, radiator, heater core, or temperature sensor? Or is it dislodging and relocating crud that could create a blockage somewhere else where it could ultimately cause engine damage? Or is it fear that you’d never get all the chemical out?
There really isn't a problem anymore like there used to be. Chemical flush detergents used to be harmful to the environment, that is until they reformulated them all. As far as the vehicle goes some are afraid that it will not rinse out completely out of the system. That can be attributed to laziness. That's why you wash once, rinse twice. Wash twice, rinse three times. Another issue is that are any chemical or detergent slush may shake loose any temporary or " permanent" sealants being used to hide coolant system issues. In a way, you actually want this to happen so that you know what you'll have to fix or replace.
 

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Discussion Starter #9 (Edited)
A quick note about service manuals: the service manual is not always correct. In fact if you take a look at one example , it's kind of really bad. For example, the AutoZone repair guides taken directly from the service manuals have entirely the wrong torques for the Equinox engine. Instead, you have to use the torque specs for the older 3400 engine from its predecessors like the Aztec and the rendezvous, or the GM minivans. If you use the torques they say for the Equinox engine, you'll damage your engine. One other thing in the service manual is that it doesn't tell you about the temperature gauge or the temperature rising really high. Seeing that often freaks out most people and they turn off the engine too early thinking that it's going to overheat. Seriously in this section, all the service manual says to do is turn on the engine until the thermostat opens and then turn it off. Nothing else. I wrote these instructions here from actual real world experience. The coolant cap trick of leaving it on until later I had to teach myself.

Anyway, I hope a lot of you find this informative.
 

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2. Pay attention to the drainage. When it slows to a slow drip, slowly unscrew the coolant cap on the bottle only enough to allow coolant to flow out of the system again via the spigot, but, do not remove yet.

LOL WUT.

This is the problem with people's how to's. They do something and think its one thing, but its not.

Once vent the system please explain the difference between slowly unscrewing it and simply taking it off. LPT: there is absolutely no reason to 'slowly unscrew' once the vacuum is broken.


The temperature will get up to just below the red mark, but, never directly on it for roughly 5-8 minutes. This is normal. The reason is that the water on one side of the thermostat is cold, while the water on the other side is hot, and, must heat the thermostat to opening temperature. This also is an indication that the thermostat is working correctly.

LOLOLOL WUT

By your explanation (which is wrong) this should happen EVERY TIME YOU START THE CAR. The water in the block is ALWAYS hotter than the water on the water pump, yet you never see this. Why? Because the wax pellet that opens the t-stat is IN THE BLOCK.

What you are seeing is AIR IN THE SYSTEM. Most aftermarket t-stats actually have a vent (it looks like a bb) to prevent this when refilling. But factory t-stat usually don't as they are filled and tested at the factory.

Also not using a chemical flush is more about not damaging the copper head gasket and aluminum heads. Some flushes are not save for aluminum or copper. Its not really about the environment, but about not eating the metals.

Nice try, but D- is about the best grade you should expect.
 

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Discussion Starter #11 (Edited)
2. Pay attention to the drainage. When it slows to a slow drip, slowly unscrew the coolant cap on the bottle only enough to allow coolant to flow out of the system again via the spigot, but, do not remove yet.

LOL WUT.

This is the problem with people's how to's. They do something and think its one thing, but its not.

Once vent the system please explain the difference between slowly unscrewing it and simply taking it off. LPT: there is absolutely no reason to 'slowly unscrew' once the vacuum is broken.


The temperature will get up to just below the red mark, but, never directly on it for roughly 5-8 minutes. This is normal. The reason is that the water on one side of the thermostat is cold, while the water on the other side is hot, and, must heat the thermostat to opening temperature. This also is an indication that the thermostat is working correctly.

LOLOLOL WUT

By your explanation (which is wrong) this should happen EVERY TIME YOU START THE CAR. The water in the block is ALWAYS hotter than the water on the water pump, yet you never see this. Why? Because the wax pellet that opens the t-stat is IN THE BLOCK.

What you are seeing is AIR IN THE SYSTEM. Most aftermarket t-stats actually have a vent (it looks like a bb) to prevent this when refilling. But factory t-stat usually don't as they are filled and tested at the factory.

Also not using a chemical flush is more about not damaging the copper head gasket and aluminum heads. Some flushes are not save for aluminum or copper. Its not really about the environment, but about not eating the metals.

Nice try, but D- is about the best grade you should expect.
Um, the cap is a 2 stage cap. The method described actually keeps the coolant system from sucking in too much air while draining and displacing it into someplace like the heater core forcing the damaging process of "burping." I have seen this first hand happen if the method you re suggesting is followed. Secondly, note the Wash once, rinse twice, wash twice, rinse 3 times denotation. The reason for that is to clean out the excess remaining detergent, while still preventing air suckage.

Also, systems don't use copper anymore, they use aluminum. The Equinox system is a plastic and aluminum system, even the heater core. The head gasket is usually graphite fiber and steel gasket as well.

If you don't like my information, try a GM technician with real world experience....


Thank you, and have a nice day.


P.S: I make it a point not to follow anyone who uses "WUT" instead of "What?", so, I'm guessing that D- is what you got in English class. First of all, please learn that I have put these instructions here for reason: No one else has..... Maybe because they are afraid of the horrible criticism they would get from people like you when they know they're doing the right thing.
 

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Lol WUT? ?

Two stage means that the cap will vent at a set pressure when hot and open to release vacuum when cool not that is opens and opens more.

Here's a list of copper parts tstat, temp sensor, water pump bushing, core plugs and I'm sure there are a few more.

You're not quite as up to speed as you think.

You don't follow people that use wut... Good. You need to be studying.
 

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Discussion Starter #13
Take note, I just recently also changed the heater core due to, well, age... it popped.... I followed the instructions with just 2 rinse cycles before the change, and then the coolant charge cycle. My method actually caused the air in the new heater core to rise into the coolant bottle and literally was able to get pushed out of the system and replaced by coolant....... This is something to keep in mind if any of you are ever brave enough to replace the heater core yourselves.
 

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Discussion Starter #14
Lol WUT? ?

Two stage means that the cap will vent at a set pressure when hot and open to release vacuum when cool not that is opens and opens more.

Here's a list of copper parts tstat, temp sensor, water pump bushing, core plugs and I'm sure there are a few more.

You're not quite as up to speed as you think.

You don't follow people that use wut... Good. You need to be studying.
Ok, I'm going to call you out on something because I'm tired of you..... If you're such an expert, then why are you begging for a service manual when nearly all of the instructions can be found online???????........

https://www.equinoxforum.net/29-1st-gen-equinox/25215-begging-2005-service-manual.html


Please, Stop bugging and stay in your lane.....

Thank you,

Starflare5.
 

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"5. After this time, you will notice the temperature start to rise slowly, the coolant fans go from low to high, yet, the air in the vent will remain cold. The temperature will get up to just below the red mark, but, never directly on it for roughly 5-8 minutes. This is normal. "

Thanks for your write up. Informative and thorough. I have checked the hash marks on the temp gauge and compared it to ECT readings as provided by the ECM. The coolant temps inside the engine are at 260-270 degrees F near the red mark on the gauge. The thermostat should open far before this point, between the 7 and 6 o'clock position normally.

I recently changed my thermostat and drained the radiator and part of the block. I experienced the same no heat and air pockets in the core and head. Temps were rising quickly and getting a lot of steam from the tank. I was able to resolve it by pulling the upper hose, and filling the radiator and head with coolant. Doing this restored normal flow through the system and I heard the core purge air up to the tank. I believe this is the procedure outline in the GM service manual.
 

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i have 2 2005 equinoxes and picked up both with bad headgaskets. i got 1 around june 1st and i think it had stopleak added. i fixed it and had almost no heat. i unhooked heater hoses where they transition into the steel pipes on top of the trans area and flushed out the lines into the heater core. i did get some darkish fluid coming out but no chunks. the heat is ok now, not great. i have been driving it daily. nox 2, which i got around labor day has super heat from day 1 after repair. i mean it is HOT. i think it would be quite easy, if you can say that, to unhook hoses again and only pour cleaner into the heater core hoses. if, i dont want to send the cleaner thru the entire cooling system.
 

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pfarber...

I've received several complains about belittling and disrespectful comments on several threads attributed to you. Those type of tactics often cause others to retaliate which can make for a battle rather than an informative discussion. I ask that you get your points across in a more polite manner which is easier for all of us to tolerate.
Thank you
IceMan
 

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Discussion Starter #19
"5. After this time, you will notice the temperature start to rise slowly, the coolant fans go from low to high, yet, the air in the vent will remain cold. The temperature will get up to just below the red mark, but, never directly on it for roughly 5-8 minutes. This is normal. "

Thanks for your write up. Informative and thorough. I have checked the hash marks on the temp gauge and compared it to ECT readings as provided by the ECM. The coolant temps inside the engine are at 260-270 degrees F near the red mark on the gauge. The thermostat should open far before this point, between the 7 and 6 o'clock position normally.

I recently changed my thermostat and drained the radiator and part of the block. I experienced the same no heat and air pockets in the core and head. Temps were rising quickly and getting a lot of steam from the tank. I was able to resolve it by pulling the upper hose, and filling the radiator and head with coolant. Doing this restored normal flow through the system and I heard the core purge air up to the tank. I believe this is the procedure outline in the GM service manual.
Yeah, did you read this part after?:

"The reason is that the water on one side of the thermostat is cold, while the water on the other side is hot, and, must heat the thermostat to opening temperature. This also is an indication that the thermostat is working correctly."

This actually happens with all closed coolant systems and can freak out most people. I know it freaked me out with past vehicles until I found out it was normal. This actually happens in most flush and fill procedures with this type of coolant system. The only time it actually does go wrong is if there is actual air in the system. In this case the vehicle will seem to over heat. if it does, shut it off immediately, wait 15 minutes, then very slowly unscrew the coolant cap to release the excess air. Continue on as usual, or, if in the Coolant Charge Cycle, remove the cap completely and add more coolant, and put the cap back. Start the engine. It will get to normal temperature, and the heat will start working.

I hope this helped clarify somethings,

Starflare5.
 
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