Coolant question

[Lala81]

Just wanted to ask some general questions about coolant. My car almost 8 years old liao. 

Was told on my last servicing that coolant was "low condition", required $60 to change. I declined as i already spent some money on changing brake fluid and also replacing my fan/serpentine belt which they said was cracked.

Servicing manual says change coolant every 30k. Car is being serviced once a year.

I thought it was just a simple top up like washer fluid or what. I didn't look inside the engine bay.
So i bought a 2L coolant bottle on 11.11 to "top up". I also watched some youtube videos, so i do know how to release the spigot valve at the bottom of the radiator for my model. To do a full change would probably require somewhere in the level of at least a a couple more litres.

Hmm today morning went to take a look when my engine was cold, but the coolant in the reservoir tank is actually above the maximum mark.
Then open radiator cap is u can see the fluid level but i know there's no marking inside.

So should i buy more coolant and do a full flush? Is the above the maximum mark coolant level in the coolant reservoir abnormal?

My engine temps dont seem to have any issue.

[Mkl22]

19 minutes ago, Lala81 said:

Just wanted to ask some general questions about coolant. My car almost 8 years old liao. 

Was told on my last servicing that coolant was "low condition", required $60 to change. I declined as i already spent some money on changing brake fluid and also replacing my fan/serpentine belt which they said was cracked.

Servicing manual says change coolant every 30k. Car is being serviced once a year.

I thought it was just a simple top up like washer fluid or what. I didn't look inside the engine bay.
So i bought a 2L coolant bottle on 11.11 to "top up". I also watched some youtube videos, so i do know how to release the spigot valve at the bottom of the radiator for my model. To do a full change would probably require somewhere in the level of at least a a couple more litres.

Hmm today morning went to take a look when my engine was cold, but the coolant in the reservoir tank is actually above the maximum mark.
Then open radiator cap is u can see the fluid level but i know there's no marking inside.

So should i buy more coolant and do a full flush? Is the above the maximum mark coolant level in the coolant reservoir abnormal?

My engine temps dont seem to have any issue.

If coolant has not been change since day1 then yes you should drain and fill. If you know where the stop cock is it is easy. Do it when cold. Get a container to catch the used coolant and pour it into a bottle for disposal. But 2 bottle of 4L premix. Should be enough. 
else just let workshop do

Edited November 20, 2022 by Mkl22

[Lala81]

6 minutes ago, Mkl22 said:

If coolant has not been change since day1 then yes you should drain and fill. If you know where the stop cock is it is easy. Do it when cold. Get a container to catch the used coolant and pour it into a bottle for disposal. But 2 bottle of 4L premix. Should be enough. 
else just let workshop do

Honestly can't remember when i last changed. maybe when it was serviced with kah motors, but pretty sure not since i started servicing outside from 60k onwards. 
I have the 2L bottle. If i buy a totachi 4L bottle (cheapest online at $20 inclusive of shipping), then i think 6L maybe enough. I know for some older civics it's about 4.7L for a full flush. But there's no information on how much is required in the owner's manual.

Quite bohua to buy another 8L of coolant.

I'm puzzled why they say its low condition, when there is excess coolant in the reservoir tank.

Edited November 20, 2022 by Lala81

[Gnahp]

my previous car did this too

in the beginning I find it is counterintuitive that the coolant level rise when the engine is cold

but I have my own theory 

when the engine is hot/warm, the rubber hoses of the cooling system soften and balloon

if you fill the coolant to the correct level when it is warm

after cooling down, the rubber hoses shrink back to the original sizes and reducing the total volume

that will push the coolant level up

 

 

 

[Lala81]

5 minutes ago, Gnahp said:

my previous car did this too

in the beginning I find it is counterintuitive that the coolant level rise when the engine is cold

but I have my own theory 

when the engine is hot/warm, the rubber hoses of the cooling system soften and balloon

if you fill the coolant to the correct level when it is warm

after cooling down, the rubber hoses shrink back to the original sizes and reducing the total volume

that will push the coolant level up

 

 

 

wah haha that makes a lot of sense. Especially the mechanics are probably doing it with an at least a warm engine bay.

[Gnahp]

16 minutes ago, Lala81 said:

I'm puzzled why they say its low condition, when there is excess coolant in the reservoir tank.

do you meant your radiator coolant level is low but the reservoir tank level is ok?

if that is the case

likely the pressure cap of the radiator need replacement (I assume your cooling system is those typical Japanese/Korean setup with pressure cap on the radiator and non pressurised expansion tank)

a working cap will allow the coolant to suck back from the expansion tank when the engine is cooling down

a defective cap will suck air instead of coolant, sometimes could be an air leakage of the small rubber hose between the radiator cap neck and the expansion tank

overtime, the coolant level in the radiator will drop but the expansion tank level stays the same

[Lala81]

24 minutes ago, Gnahp said:

do you meant your radiator coolant level is low but the reservoir tank level is ok?

if that is the case

likely the pressure cap of the radiator need replacement (I assume your cooling system is those typical Japanese/Korean setup with pressure cap on the radiator and non pressurised expansion tank)

a working cap will allow the coolant to suck back from the expansion tank when the engine is cooling down

a defective cap will suck air instead of coolant, sometimes could be an air leakage of the small rubber hose between the radiator cap neck and the expansion tank

overtime, the coolant level in the radiator will drop but the expansion tank level stays the same

I have no idea. The "low condition" is quoted by the workshop. Maybe every 30k, they will always recommend that. Though my last service was at 89k. Right now I'm around 106k.

I can still see the fluid level below my radiator cap. seems ok? 

Thanks for the diagram, so that's how the cap works. 

Edited November 20, 2022 by Lala81

[Gnahp]

2 minutes ago, Lala81 said:

I have no idea. The "low condition" is quoted by the workshop. Maybe every 30k, they will always recommend that. Though my last service was at 89k. Right now I'm around 106k.

I can still see the fluid level below my radiator cap. seems ok? 

Thanks for the diagram, so that's how the cap works. 

for me, a working cap will show coolant level to the brim when I open it

like this

if it isn't, I will replace the cap first, it is cheap

yes, the cap is a spring loaded valve

when engine warm up coolant expand and pressure build up

the extra volume will flow into the expansion tank and store temporary

when the engine cools down, the extra coolant stored in the expansion tank will get suck back to the cooling system

maintaining a closed system without air

[Mkl22]

49 minutes ago, Lala81 said:

I have no idea. The "low condition" is quoted by the workshop. Maybe every 30k, they will always recommend that. Though my last service was at 89k. Right now I'm around 106k.

I can still see the fluid level below my radiator cap. seems ok? 

Thanks for the diagram, so that's how the cap works. 

If you can see the fluid, like the picture @Gnahp posted then it’s fine. 
workshop pulling a fast one on you if they say it’s low. 
hate such workshops. 

[Lala81]

Hmm so you are saying with a higher than max level in the reservoir, it's more likely there's too much air in the system (being introduced by a leaky cap) rather than coolant being lost or evaporated?

38 minutes ago, Gnahp said:

for me, a working cap will show coolant level to the brim when I open it

like this

if it isn't, I will replace the cap first, it is cheap

yes, the cap is a spring loaded valve

when engine warm up coolant expand and pressure build up

the extra volume will flow into the expansion tank and store temporary

when the engine cools down, the extra coolant stored in the expansion tank will get suck back to the cooling system

maintaining a closed system without air

 

 

[Lala81]

1 minute ago, Mkl22 said:

If you can see the fluid, like the picture @Gnahp posted then it’s fine. 
workshop pulling a fast one on you if they say it’s low. 
hate such workshops. 

I can see it but not as high. I'm going overseas tomorrow so i don't think i have time to take a picture tomorrow am after my engine cools overnight cos I'm working today.

Edited November 20, 2022 by Lala81

[Gnahp]

1 minute ago, Lala81 said:

Hmm so you are saying with a higher than max level in the reservoir, it's more likely there's too much air in the system (being introduced by a leaky cap) rather than coolant being lost or evaporated?

 

 

that is also another possibility

don't want to confuse you first with air in the cooling system 😁

air trapped in the cooling system can do all kind of funny things to the coolant level

I also surrender

now as long as I see coolant level between MIN and MAX

I won't think and analyse too much

[zipping]

https://oils-finder.com/index.php?model_code=accord13

Anyway, had an previous car, drove for 10 yrs, nvr chg coolent b4, oni do topups w distilled water.

Edited November 20, 2022 by zipping

[Fitvip]

The coolant level should be at the brim when the cap is opened. 

When the cooling system is not functioning optimally, the coolant will be expelled through the pressure cap into the reservoir. When the temperature drops, the engine will suck back the expelled coolant from the reservoir. So, it is not necessary to fill the reservoir to the brim, giving space for the expelled liquid from the engine. It is a to and fro process. 

Unless too much coolant is expelled to the reservoir causing it to overflow, there will always be enough coolant for the engine.

Cooling system will malfunction when rust choke up the tubes or when the fan is not in order and the heat is not dispelled efficiently.

I have never changed the my coolant.

[Ct3833]

If your reservoir is full but radiator is not, just replace the radiator cap,  it should solve your problem. 

[Lala81]

are all reservoir caps one size fit all?

 

[Inlinefour]

AD told me to top up distilled water 

 

 

I drink the whole bottle 

 

don’t know correctly done 🥹

[Beregond]

3 hours ago, Lala81 said:

Just wanted to ask some general questions about coolant. My car almost 8 years old liao. 

Was told on my last servicing that coolant was "low condition", required $60 to change. I declined as i already spent some money on changing brake fluid and also replacing my fan/serpentine belt which they said was cracked.

Servicing manual says change coolant every 30k. Car is being serviced once a year.

I thought it was just a simple top up like washer fluid or what. I didn't look inside the engine bay.
So i bought a 2L coolant bottle on 11.11 to "top up". I also watched some youtube videos, so i do know how to release the spigot valve at the bottom of the radiator for my model. To do a full change would probably require somewhere in the level of at least a a couple more litres.

Hmm today morning went to take a look when my engine was cold, but the coolant in the reservoir tank is actually above the maximum mark.
Then open radiator cap is u can see the fluid level but i know there's no marking inside.

So should i buy more coolant and do a full flush? Is the above the maximum mark coolant level in the coolant reservoir abnormal?

My engine temps dont seem to have any issue.

I dun recommend u to drain out the radiator from the btm.

Its easy to drain and top up. But some time air pockets go in and  etc and the thermostat cannot open. It might cause problem that might be beyond your expertise. 

Change every 30k is too wasteful. More like every 100k.

As long as the coolant stoll got colour and at the max mark. Dun need bother about it.

If its below the min mark. Just buy same colour and top up.