A coolant circuit for an internal combustion engine includes: a coolant pump; at least one coolant line; a radiator; and a coolant cavity delimited in the internal combustion engine. The coolant pump, the coolant line, the radiator and the coolant cavity are filled with a coolant. One or more sensors, configured to monitor the coolant concentration, are fixedly and permanently arranged in and/or on the coolant circuit.

An engine coolant monitoring system for a machine is disclosed. The engine coolant monitoring system may have a test device configured to test a fluid sample of an engine coolant. The engine coolant monitoring system may also have a database configured to store a test result generated by the test device, the test result including a plurality of characteristics of the fluid sample. In addition, the engine coolant monitoring system may have a controller. The controller may be configured to access a rule-set associated with the engine coolant from the database, the rule-set having criteria associated with the characteristics. The controller may also be configured to label the engine coolant as normal when the characteristics of the fluid sample satisfy the criteria and label the engine coolant as abnormal when the characteristics do not satisfy at least one criterion included in the rule-set.

An internal combustion system includes a control device having an accumulated amount of time measuring unit that measures an accumulated amount of time by measuring an amount of time when the temperature of the coolant measured by a temperature sensor is equal to or higher than a defined temperature and accumulating the amount of time measured, an exchange determination unit that determines that the coolant needs to be exchanged when the measured accumulated amount of time reaches or exceeds an upper-limit accumulated amount of time, and an upper-limit amount of time setting unit that sets the upper-limit accumulated amount of time for determination by the determination unit in accordance with the type of metal forming the flow channel where the coolant flows.

An internal combustion system includes a control device having an accumulated amount of time measuring unit that measures an accumulated amount of time by measuring an amount of time when the temperature of the coolant measured by a temperature sensor is equal to or higher than a defined temperature and accumulating the amount of time measured, an exchange determination unit that determines that the coolant needs to be exchanged when the measured accumulated amount of time reaches or exceeds an upper-limit accumulated amount of time, and an upper-limit amount of time setting unit that sets the upper-limit accumulated amount of time for determination by the determination unit in accordance with the type of metal forming the flow channel where the coolant flows.

An example device in accordance with an aspect of the present disclosure includes a sensor, a controller, and an injector. The sensor is to provide sensor output regarding fluid chemistry of a fluid of a cooling system. The controller is to identify attributes of the fluid. The injector is to inject at least one additive into the fluid to bring at least one attribute into a threshold range.

The present invention relates to a cooling loop, in particular for a motor vehicle, the loop being configured to allow a heat exchange between a cooling liquid and a liquid to be cooled. According to the invention, the cooling loop includes an on-board sensor which is positioned at least partially in contact with the cooling liquid, the sensor being configured to supply at least one datum relating to at least one physical property and/or chemical property of the cooling liquid.

An engine coolant monitoring system for a machine is disclosed. The engine coolant monitoring system may have a test device configured to test a fluid sample of an engine coolant. The engine coolant monitoring system may also have a database configured to store a test result generated by the test device, the test result including a plurality of characteristics of the fluid sample. In addition, the engine coolant monitoring system may have a controller. The controller may be configured to access a rule-set associated with the engine coolant from the database, the rule-set having criteria associated with the characteristics. The controller may also be configured to label the engine coolant as normal when the characteristics of the fluid sample satisfy the criteria and label the engine coolant as abnormal when the characteristics do not satisfy at least one criterion included in the rule-set.

Methods and systems are provided for a cooling system for a vehicle engine. In one example, the cooling system includes a coolant solution circulated through both an engine cooling circuit and a vehicle interior heating circuit that is fluidly coupled to the engine cooling circuit, and a reservoir containing concentrated antifreeze. The concentrated antifreeze is flowed from the reservoir to the vehicle interior heating circuit via a shutoff valve to increase a concentration of antifreeze in the coolant solution. In some embodiments, a separation unit may be used to decrease the concentration of antifreeze in the coolant solution.

Methods and systems are provided for maintaining a desired engine coolant level and a relative glycol amount in the engine coolant by using water sourced from on-board vehicle systems. In one example, a method may include supplying water to the engine coolant reservoir in response to the engine coolant level decreasing below a threshold. Also, a relative glycol amount in the coolant may be maintained at a threshold amount by adding water to the coolant in response to a relative glycol increasing above the threshold.

Methods and systems are provided for maintaining a desired engine coolant level and a relative glycol amount in the engine coolant by using water sourced from on-board vehicle systems. In one example, a method may include supplying water to the engine coolant reservoir in response to the engine coolant level decreasing below a threshold. Also, a relative glycol amount in the coolant may be maintained at a threshold amount by adding water to the coolant in response to a relative glycol increasing above the threshold.