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Coolant Level

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This has probably been done to death but what is the normal operating coolant level on a mk 7.5 ecoboost.

I read some stuff on line about coolant loss and started to look more closely at mine.

At the moment its level with the horizontal joint of the expansion bottle but had topped it up to closer to the max line a couple of weeks ago.

The car's warranty runs out in December - should I get it checked by the dealer now or is it nothing  to worry about?

 

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From what I understand about cooling systems with expansion tanks , the coolant level will drop to a specific level where equilibrium happens , and then stick to that level , its a pressurized system and the tank cap is actually a pressure cap that keeps the coolant pressure constant according to factory specs, when pressure is high enough the cap valve opens to vent vapour out, which causes coolant loss, this continues to happen until the amount of coolant in the system when expanded creates a max pressure that meets the factory specs ( which I think is 21 psi ) and then the system reaches a state of equilibrium and no loss again happens, if you tried to top up to the max mark it will drop again to the same level and then stays there, and the max mark is not there to top up to it , its there so that the coolant level when the engine is cold should be between it and the min mark, when engine gets hot the coolant level rises to the max and may be above the max by a little bit, when it gets cold again it will drop down to the same specified level , if that's the case with you I guess you have no problems.

By the way , mine is 2019 mk8 1.0 ecoboost, when it was new the coolant level was way above the max , now after 5 months and 9000 km the level is between the min and the max and it stayed there, so if that's the case not need to worry

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My car is 2015 model mk7.5 and its coolant level has fluctuated between over MAX and close to MIN. Never had to refill it though.

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I’ve been going on this for coolant levels:

When engine is cold, the coolant should be just above the minimum line. 

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Agree with Ahmad. Nicely explained. Owned a few cars with expansion tank cooling systems over the years and in every case the coolant has found an equilibrium level (around the minimum mark when cold, usually). Don't worry, but keep an eye on it as normal.

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59 minutes ago, fleamoo said:

Agree with Ahmad. Nicely explained. Owned a few cars with expansion tank cooling systems over the years and in every case the coolant has found an equilibrium level (around the minimum mark when cold, usually). Don't worry, but keep an eye on it as normal.

well me too , I had a 1996 Skoda Felicia for almost 22 years , it has an expansion tank also , and this was the case with it , at first I was worried , I used to top up every time the level drops, but as years passed I was sure its normal, it reached a specified level and stayed there , never had to top up again until its time to replace the coolant 🙂 

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