The coolant is added to the engine bay’s expansion (overflow) reservoir, not directly into the radiator, and you should do it only when the engine is cold. Use a 50/50 premixed ethylene glycol coolant that meets Hyundai’s specifications. This guide explains where to put coolant, what kind to use, and how to fill safely.
Understanding the correct process helps prevent overheating, coolant leaks, and damage to the cooling system. The reservoir is a translucent tank with MAX and MIN marks, and the radiator cap should remain closed while you’re adding coolant unless directed otherwise by the manual.
Locating the coolant reservoir
The expansion reservoir is located in the engine compartment, typically on the side of the radiator. It is a translucent plastic tank with a labeled cap and MAX/MIN level indicators. You’ll fill coolant into this reservoir rather than pouring directly into the radiator.
How to add coolant
Follow these steps to safely fill the coolant in a 2013 Sonata. This list is designed to be followed in order.
- Park on level ground and turn off the engine. Do not open any cooling system cap while the engine is hot; wait at least 15 minutes for it to cool.
- Locate and gently twist the reservoir cap only when it is cool enough to touch. If you’re unsure, leave the cap in place and proceed to check the level with the engine cold.
- Check the coolant level on the side of the reservoir. If the level is below the MIN mark, plan to add coolant.
- Pour coolant into the reservoir until the level reaches the MAX line. If you are using concentrate, premix it with distilled water to a 50/50 ratio before adding.
- Replace the reservoir cap securely and ensure it is seated properly.
- Start the engine and let it reach operating temperature, then check for leaks. If you had to add a significant amount of coolant, recheck the level once the engine cools again and top off if necessary.
Closing note: After filling, monitor the coolant level for a few days to ensure there are no leaks or abnormal drops in level.
Choosing the right coolant
Using the correct coolant helps protect the aluminum engine components and ensures proper corrosion resistance. Use Hyundai Genuine Long-Life Coolant or an equivalent 50/50 premixed coolant that meets Hyundai/Kia specifications. Do not mix incompatible coolant formulas, and when diluting concentrates, use distilled water rather than tap water.
- Opt for a 50/50 premixed ethylene glycol coolant formulated for Hyundai/Kia engines (Hyundai Genuine Long-Life Coolant or an equivalent that meets the manufacturer’s specs).
- If starting with concentrate, mix it with distilled water to achieve a 50/50 ratio before pouring into the reservoir.
- Avoid mixing different types of coolant, and do not add straight water in freezing conditions unless you are following the manual’s emergency guidance.
Summary of coolant choice: select a product that is labeled compatible with Hyundai vehicles, premixed to 50/50, and use distilled water to dilute concentrates if required.
Safety and maintenance tips
Always handle coolant with care. Wear gloves if you’re handling concentrate, clean up spills immediately, and store coolant out of reach of children and pets. Dispose of old or unused coolant at a proper recycling facility. If you’re unsure about any step or notice persistent overheating, coolant loss, or leaks, consult a mechanic.
Summary
To add coolant to a 2013 Hyundai Sonata, use the engine bay expansion reservoir, ensure the engine is cold, check the MAX/MIN marks, and fill up to the MAX line with a 50/50 premixed coolant that meets Hyundai specifications. Avoid opening caps when hot, and verify the system for leaks after filling. Always follow the owner’s manual for exact coolant type and maintenance procedures.
Where is the coolant in a Hyundai Sonata?
And or water as specified in your owner's. Manual take care when adding coolant as it can damage the paintwork on your car if you do spill a bit wash it off thoroughly with clean. Water.
Where do you put coolant in a 2013 Hyundai Sonata?
Cool hasn't ran in a while so we know we need to add. So you do is open the top. Here. All right guys now if you don't have a funnel one thing you can do is cut a water bottle.
Is it okay to drive my Hyundai with low coolant?
Driving with low coolant, even for a short distance, risks overheating and engine failure. Call Westside Hyundai at (904) 440-1668 or Schedule Service online for a thorough coolant system check and repair.
Can I just pour coolant into the reservoir?
To top up your engine's coolant, you can simply open the reservoir cap (be careful the engine is not too hot and use a cloth wrapped around the cap to open it, as there could be some residual pressure left in the system) and add to the fluid level – what you use to do this is very important though.