My Radiator Coolant is leaking - What Should I Do?

How do I know if my car is leaking radiator coolant? There are several signs to look out for if you think that your car is leaking radiator coolant. If it is a small leak, you may be able to fix it using a sealant preparation which you can purchase from a reliable shop. More complicated problems such as leaks in the radiator seam or leaks in cars with plastic coolant tanks should be repaired by a professional.  If your car is leaking radiator coolant then call us for help.

"Awesome service! Great place to have all your vehicle maintenance done. Would highly recommend Hansma Automotive." - Kathy

More Testimonials

Signs your car is leaking radiator coolant

  • Your temperature gauge rises. This is the gauge on your dashboard that indicates how hot your engine temperature is.
  • There is a pool of coolant under your car. Coolant is the liquid used in the cooling system. It is usually green, red, orange, blue or rust coloured.
  • Your radiator level drops. A radiator helps to remove heat from your engine. Liquid coolant moves through the passageways of your radiator helping to dissipate the heat. If the amount of coolant decreases, then there may be a leak.
Topping up Coolant      Photo courtesy of Fir0002/Flagstaffotos   

Topping up Coolant      Photo courtesy of Fir0002/Flagstaffotos   

To determine where the leak is you should check the following.

WARNING: Always take extreme precaution if you are checking the cooling system for excessive heat and the possibility of burns. Allow the vehicle to cool down before removing the radiator cap.

  • The Radiator: If you notice whitish spots or rust-coloured stains, these may be evidence of leaks which have dried. You can also feel under the radiator for signs of leakage.
  • The Pressure Cap: Ask a reliable mechanic to test the pressure cap. Replacing a defective cap could be an easy and inexpensive fix for the problem.
  • The Hoses: Check the hoses for cracks, pinholes and other signs of deterioration. Replace any defective or damaged hoses immediately.

What to do if your radiator has a bad leak

If your leak is a minor one try purchasing a radiator sealant. This product when poured into your radiator will form a coating on the walls and will fill any tiny holes or "pin pricks". Simply follow the instructions on the box. Most sealants take at least 12 hours to properly set. 

If your radiator has a bad leak you should go to a reliable mechanic. You may find that it is actually cheaper to replace the radiator than to get it repaired. Never take chances with a radiator that is leaking coolant. Failure to repair the vehicle may cause considerable damage to the engine and other components, resulting in expensive repairs.


Call or Text: 519-748-5533

Why Choose Hansma Automotive?

At Hansma Automotive, we care about you and your car.  We truly believe in honesty, reliability, and exceptional service. Hansma has been in existence since 1987 and weare proud to have established a trustworthy reputation with our clients. We are located at 88 Shoemaker Street in Kitchener, Ontario.


Checking For Coolant Leaks

How To Find Leaks In Your Vehicle's Cooling System

Troubleshooting Cooling System Leaks   

Car Repair: How to Use Radiator Sealant

Posted on April 4, 2016 .