It’s important the coolant, also known as antifreeze, is in good condition so cooling system parts like the radiator can work in colder weather and don’t break. Our expert mechanics in this post and video review how to use an antifreeze tester, which tests the condition and strength of the antifreeze by measuring its freezing point and its mixing ratio of water and coolant.
Why Check the Condition of the Antifreeze?
It’s important to check the condition and strength of the antifreeze, also known as the coolant. You may not know the history of a recently purchased car, or maybe you haven’t had the maintenance done recently.
Why Does Coolant Need a Low Freezing Point?
You want to make sure the coolant has a low freezing point so parts can function in colder weather. If the coolant is in bad condition, cooling system parts like the radiator can crack or you can experience engine damage.
How to Use an Antifreeze Tester to Check the Condition of Antifreeze
An antifreeze hydrometer or tester can help you diagnose the coolant’s condition. It will draw coolant in and measure the freezing point of the coolant and its ratio of coolant and water.
Steps for How to Use an Antifreeze Tester
- Draw Coolant into the Hydrometer from the Coolant Overflow Tank
Insert the hydrometer into the coolant overflow tank and draw coolant to measure it
- Tap the Hydrometer If Needed to Get the Dial Moving
Give the hydrometer a couple light taps if needed to get the dial moving
- Record the Measurement
Take note of the measurement, which will point to the freezing temperature and the mixing ratio of water and antifreeze
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