Cooling System Leaks: An FAQ

Your car depends on its cooling system to maintain safe engine temperatures. If you suddenly see a dashboard warning light or a spike in your engine temperature needle that warns of overheating, a leak somewhere in the system may have allowed crucial liquid coolant to escape, either gradually or all at once.

You'll feel less mystified about your cooling system trouble once you understand how these systems work, why and where they can develop leaks, how to recognize a leak in progress, and how your auto technician can find and fix such leaks. Check out the answers to frequently asked questions about cooling system leaks.

How Does a Healthy Cooling System Normally Store and Use Liquids?

Automobile engines generate tremendously high temperatures, with their spark plugs setting off thousands of explosions per minute to keep the pistons moving. Most modern vehicles control this heat by circulating a liquid coolant from the water pump through the heater core to the thermostat by way of hoses.

During this trip through the engine components, the coolant (a mixture of antifreeze and water) absorbs the surrounding heat the engine generated. The heated coolant then passes from the thermostat into the radiator, where incoming air from the vehicle's front grille cools it off.

Once the coolant has shed its heat, it passes through a transmission cooler as it exits the radiator. A hose then carries it back to the water pump. An additional supply of coolant sits in a nearby reserve tank.

Why and Where Do Cooling Systems Leak?

Any of the components in a car's cooling system can theoretically leak coolant. In many cases, an aging hose may grow either hard and brittle or soft and spongy. The weakened hose eventually cracks or breaks, allowing its contents to escape. If this causes a serious loss of vacuum pressure, your engine may fail suddenly.

A cracked radiator can leak coolant. Rust, road debris accumulation, years of exposure to heat and cold, or a thermostat malfunction may contribute to cracks developing. The water pump or head gasket may also spring a coolant leak.

How Can You Spot a Cooling System Leak?

A sudden hose failure can give you a dramatic warning of a coolant system leak. You'll probably see a massive cloud of steam billowing out of your car if this problem occurs. The dashboard warning signals mentioned above should alert you to pull over and turn off your engine as quickly as you reasonably can.

A more subtle radiator, hose, or water pump leak will usually leave telltale puddles of antifreeze beneath your parked car. Depending on the antifreeze your particular vehicle uses, the puddles may appear pink, orange, lime-green, or blue-green in color. If you smell a sweet odor in or around your car, look for these puddles.

Small radiator leaks may leave signs of their presence on the radiator itself. Rust spots or strange, white-colored stains may mean that the radiator has leaked coolant, which then dried on the radiator's surface instead of dripping onto the ground.

A low coolant level provides another clue that you might have a cooling system leak. If the coolant in the reserve tank has dropped below the normal level (marked by lines inside the tank), you might need to check the car for a leak.

How Do Automotive Technicians Deal With Leaky Cooling Systems?

Automotive technicians know all the possible failure points in a vehicle's cooling system. Your car care expert will inspect the radiator, engine block, water pump, heater core, transmission cooler, and hoses for any signs of cracks or leaks. Pressure testing and a thermostat check can also help pinpoint the underlying problem.

With luck, your technician may solve your coolant leak problem simply by fixing or replacing a hose, or perhaps by replacing a faulty thermostat. More complicated repairs may include replacing the radiator, water pump, or head gasket.

Kell Radiator Service can handle any cooling system issues your car may encounter, from rusty radiators to holey hoses. Contact us today for a free estimate.