Coolant reservoir is full and radiator is empty why is it not circulating?
Hi Tiffany,
The engine coolant does not "circulate" through the reservoir in your Jeep. This system works on the fact that things expand when they are hot and contract when they are cold. When the radiator is full, the coolant expands when the engine gets hot and the overflow runs down the small hose to the reservoir. When you shut the engine off, the coolant contracts and a vacuum is created inside the radiator causing fluid to be drawn out of the reservoir and into the radiator. When you start your engine and it gets hot, the cycle begins again.
If the radiator is empty, this sytem cannot work. There will not be enough vacuum generated in the radiator to draw the fluid from the reservoir (too much empty space and not enough coolant contracting as it cools).
You need to find out WHY the radiator is low. If it is low, there is a reason for it. Either something is leaking EXTERNALLY like a hose or water pump, or something is leaking INTERNALLY like a blown head gasket or a cracked cylinder head. Proper diagnosis is recommended.
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