Overflowing coolant reservoirs can be dangerous. A coolant reservoir is likely to be present in a vehicle with a traditional liquid-cooled combustion motor. The coolant reservoir, which is a container used to temporarily store expanded coolant, is designed for vehicles with a traditional liquid-cooled combustion engine. The coolant will expand as the coolant heats inside your vehicle's engine. This coolant volume will then be directed to the coolant reservoir until it cools and contracts.
There are situations where the coolant reservoir may overflow. The coolant could spill from the top and cause your vehicle to overheat.
The thermostat can cause the coolant reservoir to become clogged. The thermostat can be described as a small temperature-based valve. It allows coolant to flow through it or blocks it depending on its temperature. Once the coolant reaches a specific temperature, usually between 190 and 200 degrees Fahrenheit, the thermostat will automatically open.
It is possible for thermostats to become stuck. The thermostat can become stuck in your vehicle. Coolant will not be able to flow through it. Instead, the coolant will continue heating up and expanding before the thermostat. The excess coolant will then get into your coolant reservoir, where it can spill over the top.
Your vehicle's coolant reservoir can overflow if combustion gasses leak into it. Combustion gases must follow a straight line. The combustion chamber of your vehicle will produce combustion gases as the engine burns gas and air. These combustion gases then enter the exhaust pipe, where they are expelled from your tailpipe.
A cracked engine block, or a blown header gasket, can lead to combustion gas leaks. Combustion gases can escape from your vehicle's combustion chamber if it has a cracked or blown head gasket. As the combustion gasses fill the cooling system, the coolant will push into the reservoir.
Even if your vehicle doesn't have a stuck thermostat or a leak of combustion gases, it could still be suffering from a blocked radiator. Your radiator is probably the most important component of your vehicle's cooling system. Heat will be released as coolant flows through the radiator. The radiator will cool the coolant.
Radiators can become blocked by rust particles or sediment. These blockages can lead to a backup in the coolant. This excess coolant can then leak from your coolant reservoir until the blockage has been cleared.