Coolant level going down

[Yeobh]

@Kklee Some shops have coolant hydrometer mixture testers which can detect the glycol coolant and distilled water mixture ratio. The best mixture is 50:50 but for some situations car owners / mechanics prefer 70 : 30 ratio. 

 

[Kklee]

On 6/25/2024 at 3:21 PM, Yeobh said:

@Kklee Some shops have coolant hydrometer mixture testers which can detect the glycol coolant and distilled water mixture ratio. The best mixture is 50:50 but for some situations car owners / mechanics prefer 70 : 30 ratio. 

 

IMHO.
If need, I will opt for 70:30.   Best is premixed. 🤣

[Yeobh]

@Kklee 

50/50 mixture - the coolant will boil at 107 deg C (228deg F) and freeze at -37deg C (-34deg F)

70/30 mixture - the coolant will boil at 135 deg C (276deg F) and freeze at -64deg C (-84deg F)

Solution with more than 70% antifreeze will give less protection.

70 : 30 is best for tropical countries & old vehicles where the owners can top up with distilled water as when the coolant level drop.

[Kklee]

On 6/25/2024 at 4:02 PM, Yeobh said:

@Kklee 

50/50 mixture - the coolant will boil at 107 deg C (228deg F) and freeze at -37deg C (-34deg F)

70/30 mixture - the coolant will boil at 135 deg C (276deg F) and freeze at -64deg C (-84deg F)

Solution with more than 70% antifreeze will give less protection.

70 : 30 is best for tropical countries & old vehicles where the owners can top up with distilled water as when the coolant level drop.

IMHO.
Which one is more effective in removing heat -  70/30 or 50/50 ? 

[Mkl22]

On 6/25/2024 at 4:02 PM, Yeobh said:

@Kklee 

50/50 mixture - the coolant will boil at 107 deg C (228deg F) and freeze at -37deg C (-34deg F)

70/30 mixture - the coolant will boil at 135 deg C (276deg F) and freeze at -64deg C (-84deg F)

Solution with more than 70% antifreeze will give less protection.

70 : 30 is best for tropical countries & old vehicles where the owners can top up with distilled water as when the coolant level drop.

boiling points are only half the story.

https://www.motortrend.com/how-to/glycol-or-water-coolant/

water is still by far the best in removing heat which is why racers use 100% distilled water.

 

[Mkl22]

On 6/25/2024 at 4:17 PM, Kklee said:

IMHO.
Which one is more effective in removing heat -  70/30 or 50/50 ? 

70% water and 30% glycol is better.  30% glycol should have enough protection of the water pumps and anti corrosion.

i used Meyle coolant, a made in germany reputable brand. you can google to see the mixing ratios. only says 1 coolant:1 water, 1 coolant: 1.5 water, 1coolant:2water

[Yeobh]

@Kklee 70:30 allows higher coolant boiling point. Pressure cap with std rating of 0.9kg/cm2 will allow coolant to boil above 100C ( not sure how many degree C ) Heat removal depends on yr radiator size, conditions and cooling fan speed & etc

[Kklee]

On 6/25/2024 at 4:18 PM, Mkl22 said:

boiling points are only half the story.

https://www.motortrend.com/how-to/glycol-or-water-coolant/

water is still by far the best in removing heat which is why racers use 100% distilled water.

 

IMHO.
If I can and dare, I will use distilled water and Redline Waterwetter. 🤣

[Kklee]

On 6/25/2024 at 4:29 PM, Yeobh said:

@Kklee 70:30 allows higher coolant boiling point. Pressure cap with std rating of 0.9kg/cm2 will allow coolant to boil above 100C ( not sure how many degree C ) Heat removal depends on yr radiator size, conditions and cooling fan speed & etc

IMHO.
In my experience, coolant temp seldom exceed 100°C.   The challenge therefore will be what normal operating temperature one wants to run.  If 70/30 runs cooler,  it maybe detrimental to the car engine.    Hybrid makes the matter worse - quite difficult to reach 90°C. 

[Gnahp]

On 6/25/2024 at 4:53 PM, Kklee said:

IMHO.
In my experience, coolant temp seldom exceed 100°C.   The challenge therefore will be what normal operating temperature one wants to run.  If 70/30 runs cooler,  it maybe detrimental to the car engine.    Hybrid makes the matter worse - quite difficult to reach 90°C. 

the coolant temperature below 100°C you see is more like a "consolidations" number, due to the placement of the temperature sensor

there are some areas in the engine run hotter than others

i.e. around exhaust valve area and turbocharger (water cooled)

those areas will have pocket of coolant temperature above 100°C

[Mkl22]

Never seen any manufacture recommend 70% coolant 30% water. 🤣

[Kklee]

On 6/25/2024 at 5:18 PM, Gnahp said:

the coolant temperature below 100°C you see is more like a "consolidations" number, due to the placement of the temperature sensor

there are some areas in the engine run hotter than others

i.e. around exhaust valve area and turbocharger (water cooled)

those areas will have pocket of coolant temperature above 100°C

IMHO.
I think there will be pockets near the inner surfaces that the coolant will be higher temp,
but as long as the coolant thermostat is working correctly, the coolant will be quickly circulated away.

In my observations,  to be effective in cooling,  besides the coolant,  also need to look at EO and AC on/off. 
Some vehicles may run hotter when AC is off.

[Mkl22]

On 6/26/2024 at 8:56 AM, Kklee said:

IMHO.
I think there will be pockets near the inner surfaces that the coolant will be higher temp,
but as long as the coolant thermostat is working correctly, the coolant will be quickly circulated away.

In my observations,  to be effective in cooling,  besides the coolant,  also need to look at EO and AC on/off. 
Some vehicles may run hotter when AC is off.

You may run cooler with ac as the fan is always on vs triggered by the temp sensor. But then don’t forget you also get more heat released by the ac condenser. 
the 60 70s cars that were imported from Europe suffered overheating when Aircon was added. 

Edited June 26 by Mkl22

[Kklee]

On 6/26/2024 at 9:55 AM, Mkl22 said:

You may run cooler with ac as the fan is always on vs triggered by the temp sensor. But then don’t forget you also get more heat released by the ac condenser. 
the 60 70s cars that were imported from Europe suffered overheating when Aircon was added. 

IMHO.
Last time my kimchi-american car,   the ECU trigger the fan differently.   If got AC,  the fan will be trigger earlier, IIRC,  97.  If no AC, it will trigger later 99 or was it 103.  I think the programming is such that,  if no AC, means in winter, so let the car become hotter. 🤣

Actually I think quite true Euro cars suffer from heat issues.  But may not be related to AC.  My colleague's Peugeot,  the ECU died - i think the engine bay too compact,  no ventilation. 

[boonhat_91]

Is it ok to top up original coolant if I cannot 100% ascertain what coolant is in my car? If following the maintenance schedule from mazda, 100k servicing supposed to replace coolant. My (secondhand) car did 100k servicing at 76k mileage according to AD, so is it safe to assume that the coolant was replaced then, and with the original mazda FL22 coolant? I want to top up the reservoir a bit, can I just buy the mazda FL22 and pour in?

Worst case scenario, if the coolant in my car is some OEM or aftermarket one, what damage could I expect?

[Beregond]

On 7/26/2024 at 11:03 AM, boonhat_91 said:

Is it ok to top up original coolant if I cannot 100% ascertain what coolant is in my car? If following the maintenance schedule from mazda, 100k servicing supposed to replace coolant. My (secondhand) car did 100k servicing at 76k mileage according to AD, so is it safe to assume that the coolant was replaced then, and with the original mazda FL22 coolant? I want to top up the reservoir a bit, can I just buy the mazda FL22 and pour in?

Worst case scenario, if the coolant in my car is some OEM or aftermarket one, what damage could I expect?

Can mix . Dun worry.

But make sure use same colour. And check your coolant make sure its not those concentrate tyre. Best is buy pre mix ready and top up 

If u see the level like 5mm less then max. And u really buay ta han. Just top up with pain 💧.  

But if your coolant level keep going down. And u need top up every week. Mean something wrong already. 

By right dun need to do any top up .

[Jamesc]

Not safe to assume coolant changed during service unless you see bill saying coolant changed.

Top up a bit just just use distilled water from supermarket.

Full change coolant use this.

On 7/26/2024 at 11:03 AM, boonhat_91 said:

Is it ok to top up original coolant if I cannot 100% ascertain what coolant is in my car? If following the maintenance schedule from mazda, 100k servicing supposed to replace coolant. My (secondhand) car did 100k servicing at 76k mileage according to AD, so is it safe to assume that the coolant was replaced then, and with the original mazda FL22 coolant? I want to top up the reservoir a bit, can I just buy the mazda FL22 and pour in?

Worst case scenario, if the coolant in my car is some OEM or aftermarket one, what damage could I expect?

 

[jackduke191491]

It's concerning when your coolant level drops after servicing.The workshop's explanation that air pockets might have caused the coolant level to drop as the system stabilizes is plausible.However, keep monitoring the levels closely over the next few days. If the coolant continues to drop, it could indicate a more serious issue like a leak or a problem with the radiator cap or head gasket. It is good that you’re being cautious—better safe than sorry.

Edited August 2 by jackduke191491