Coolant Confusion

Texasrules

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Hi Everyone,
Maintenance minder popped up for my coolant, tested the coolant with a test strip and it indeed needs replaced (acidic).

For people who DIY, do you just drain the radiator and fill? A bit confused on the process tbh.

Also, what's up with this fluid lasting ~2 years?

TIA
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NHCivicGuy

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Hi Everyone,
Maintenance minder popped up for my coolant, tested the coolant with a test strip and it indeed needs replaced (acidic).

For people who DIY, do you just drain the radiator and fill? A bit confused on the process tbh.

Also, what's up with this fluid lasting ~2 years?

TIA
Haven’t had to replace mine yet but in my experience coolant and brake fluid is one of those items that should be replaced every few years. Have I followed that with other used vehicles I’ve had? No but with this one I’ll definitely be following it to ensure car is in tip-top shape.
 
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Texasrules

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My Si is over 5 years old 78k miles and i’ve yet to see this maintenance minder pop up.
That's wild. Mine only needs replaced because of the acidity/age of it and it's a 2020. A bit worried haha. I think the manual also says like 2-3 years.
 

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That's wild. Mine only needs replaced because of the acidity/age of it and it's a 2020. A bit worried haha. I think the manual also says like 2-3 years.
I bought it with 20500 miles on it and the previous owner had it for 20 months. Maybe the dealership did it, but i doubt it. I’ve always heard to do it every 5-6 years on a honda.
 


SDAlexander8

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So I havent read the service manual on how to do a proper coolant change on this car. However, from what I understand, a proper flush requires several plugs to be pulled from the engine block, radiator, and maybe a couple hoses to get all of the coolant out at once.

Otherwise you’ll be doing the dilution method, where you drain the radiator, refill, run the car, repeat until the fluid looks as fresh as you want it.

I’ve considered letting a dealership do it for a couple hundred bucks rather than worry about it myself. But there is no guarantee they wouldn’t do a shortcut method as well and lie to your face.
 
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Texasrules

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So I havent read the service manual on how to do a proper coolant change on this car. However, from what I understand, a proper flush requires several plugs to be pulled from the engine block, radiator, and maybe a couple hoses to get all of the coolant out at once.

Otherwise you’ll be doing the dilution method, where you drain the radiator, refill, run the car, repeat until the fluid looks as fresh as you want it.

I’ve considered letting a dealership do it for a couple hundred bucks rather than worry about it myself. But there is no guarantee they wouldn’t do a shortcut method as well and lie to your face.
Exactly my thought, no guarantee a shop or dealership actually fully flushes it. If they shortcut and do a drain and fill...I can easily DIY that for $30.
 

latole

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My Si is over 5 years old 78k miles and i’ve yet to see this maintenance minder pop up.
If you go to the dealer for car maintenance ;

The dealer may have reset all the functions of the MM instead of just the "change oil" function when changing oil for example.

Deleting the all the MM tracker
 

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So I havent read the service manual on how to do a proper coolant change on this car. However, from what I understand, a proper flush requires several plugs to be pulled from the engine block, radiator, and maybe a couple hoses to get all of the coolant out at once.

Otherwise you’ll be doing the dilution method, where you drain the radiator, refill, run the car, repeat until the fluid looks as fresh as you want it.

I’ve considered letting a dealership do it for a couple hundred bucks rather than worry about it myself. But there is no guarantee they wouldn’t do a shortcut method as well and lie to your face.
Most all dealerships and shops do a drain and fill. Nobody pulls out plugs and hoses unless they have never worked on a car before and are reading off the internet.
 
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Texasrules

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Most all dealerships and shops do a drain and fill. Nobody pulls out plugs and hoses unless they have never worked on a car before and are reading off the internet.
Yeah so I might as well DIY it. My concern is there'd still be a good bit of old coolant in the system. Maybe drain and fill twice or nah?
 


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Yeah so I might as well DIY it. My concern is there'd still be a good bit of old coolant in the system. Maybe drain and fill twice or nah?
It's just like an oil change, you won't get all of it out but you'll get most of it. Just drain and fill and drive normal till it's due again.
 

latole

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It's just like an oil change, you won't get all of it out but you'll get most of it. Just drain and fill and drive normal till it's due again.

You are 100% right

And concerning the oil change, we would be surprised how much old oil remains in the engine if we do not do it ourselves.

I wait 1 hour before putting the cap back on and all this time oil is flowing, not much but a little. The "mechanics" do it in 5 minutes .......
 

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If you are changing either the coolant or oil, if you change it at the recommended time, I think a drain and fill is fine, as the fluid should still have some life left. But if you or the previous owner did not change at the recommend time, you may need to drain and fill, run the car, and do it again.
 

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Most all dealerships and shops do a drain and fill. Nobody pulls out plugs and hoses unless they have never worked on a car before and are reading off the internet.
You get 50% of the coolant out by opening the radiator drain. The other 50% gets out by removing the block plug which is also the location for then block heater. I did this so I know first hand also this is what manual says. I also did just the radiator swap so I measure how much came out of radiator. You must also burp the System be milking or massaging the radiator hoses for a pretty long time. Also help if front is inclined while massaging.
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