How to Fix a Radiator Leak

Radiators are primarily designed to transfer heat by thermal radiation, the main objective is heating and cooling. Whether you are on the road or in your driveway, there are simple steps to temporarily repair a radiator leak. A radiator leak should be remedied quickly because there could be extensive damage to carpets or floorboards if it is left unrepaired.

Radiator leaks can be easily prevented through proper maintenance of the radiator which is helpful in stopping the leakage. Here is how you can fix your car radiator easily.

Things Needed

  • Duct tape
  • Ground black pepper

Radiator Leak


Step 1:

First, identify the leak by looking at for path. The car radiator might not need any fixing, the cause of the leak may be one of the hoses. For checking, open the bonnet and start the engine until it gets warm. A leak will be seen immediately if it’s a hose. The hose would have to be replaced and it’s not too expensive to fix.

Step 2:

The area around the radiator cap has to be checked for leaks. If there is any presence of liquid, then a new cap or an additional gasket would be needed.

Step 3:

The leak on the outside has to be patched, if the radiator is leaking from the seam. A metal patching product has to be used, it is usually like a putty product that hardens overnight. The putty has to be placed on the leaking seam and give it some to harden and then it can be tested. This will temporarily fix the radiator.

Step 4:

A leak stop additive should be used with an anti-freeze for fixing it easily. The manufacturer’s directions can be simple followed. Many products require adding the stop leak and drive till the engine gets warmed up.

Step 5:

The radiator would have to be drained if you are using an additive that cannot be mixed with coolant. The radiator has to be flushed with plain water and then filled with water. The additive has to be mixed and drive for about 80 miles for allowing it to work. The radiator has to be drained again and let it dry. Refill it with coolant and the leak will be sealed.

Step 6:

Now, the overfill bottle should be glued if the leak shoots from a hole or cracks in it. An epoxy made for plastic can be used for filling the holes.

Tips and Warnings

  • If the radiator hose is leaking and a repair shop is not near, wrap the hose with duct tape.
  • Always carry some extra water with you in the car so that you can quickly fix a leak if it happens.
  • Carefully read the label of any additive to make sure that it’s completely safe for your car.
  • Make sure that the engine is cool before opening the radiator cap.
  • You can also make use of some white eggs to prevent radiator leaks because it works in the same way as pepper.

Further Readings: