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Helo ,
I have recently noticed that the water level of my car reservoir tank is dropping whenever I drive .
So I top it up daily , usually will be less than a half of the tank .
I tried figuring out the problem and noticed that the radiator cap rubber has harden and shape had been out of place .
Its a 0.9kg pressure big sized cap . So it was replaced .

The water level then never dropped in the reservoir tank after the change .
I thought it was done , when then the water level of the...