Why would the coolant reservoir be empty?

Your Engine’s Cylinder Head Gasket is blown. This is causing the engine to consume/burn the coolant. This is the reason your coolant auxiliary tank is always empty. The boiling out of water also happens due to this.

Should my coolant reservoir be empty when hot?

Wait until the radiator has cooled. Opening it hot can cause serious burns (very hot coolant can spray out). Turn the radiator cap counterclockwise, but don’t press down on it. Top off the coolant reservoir.

What would cause coolant not to circulate?

A thermostat could stick closed; if the wax element has been damaged by overheating or corrosion. Possible overheating from loss of coolant; a defective electric cooling fan or fan clutch. Furthermore, this failure prevents the flow of coolant to the radiator; possibly overheating the engine and causing damage.

Should the coolant reservoir always be full?

Your coolant reservoir tank should be at least 30\% full. To prevent engine overheat, ensure you check your radiator and coolant level regularly. If you notice your temperature gauge is going high while driving, you have to pull over, turn off your car. And allow your engine temperature to cool down.

How much does coolant expand when hot?

Thermal expansion occurs as coolant accumulates heat from the engine. The 6\% of the expansion volume is calculated from the amount that the coolant level will rise at 212 degrees F. This takes into account the density change of the coolant itself and all the components that are in the coolant system.

How can I tell if my coolant is circulating?

Also, touch the lower radiator hose, after the engine has reached operating temperature. If the lower hose is hot to the touch, coolant is circulating. If the lower hose is not hot, it’s possible the radiator is restricted.

How much coolant should be in an expansion tank?

Your coolant reservoir tank should be at least 30\% full. Most reservoir tank has min and max mark drawn on the side of the container. The most common cause of a coolant leak is a bad radiator cap, bad radiator fans, and loose radiator hose clamps.

How much coolant should be in the expansion tank?

The general rule of thumb for proper capacity of expansion is 12\% of total coolant volume for draw down and 6\% of the total volume for thermal expansion. Drawdown capacity is the amount of coolant that can be lost before air reaches the water pump and is introduced into the system.