I am not sure someone is trying to make this overheat as this reservoir should just have a small line running from the radiator cap opening to the overflow bottle.
Take a look at the diagram attached below and it shows where this line comes from. Sounds like someone just ran the line to some other tank for some reason. Did you just buy this vehicle?
Also, is the vehicle actually overheating?
https://www.2carpros.com/articles/symptoms-of-an-overheating-engine
https://www.2carpros.com/articles/engine-overheating-or-running-hot
If so we need to figure out why by taking a look at the guides above.
Let us know what questions you have. Thanks
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Sunday, December 20th, 2020 AT 2:04 PM