Coolant Leak Repair Cost

Coolant, or antifreeze, keeps your car’s engine from overheating.

If the motor runs too hot for too long, it can seize or crack, leading to repair costs of up to $10,000 in some models. For these reasons and more, it’s best to handle coolant leaks before they escalate.

How much does it cost to fix a coolant leak?

Repair costs depend on the cause of the leak. For instance, replacing a leaky radiator clamp can cost just $15. But if the leak stems from a blown head gasket, repair costs can reach $1,000 to $2,000 or more.

Before you can fix a coolant leak, you’ll have to find what’s causing it.

In this guide, I cover everything you need to know about coolant leaks, including causes, repair costs, and more.

5 Coolant Leak Causes And Repair Costs For Each

Damaged Radiator

Your car’s radiator sits in front of the engine for optimal airflow and cooling.

Yet, this also leaves it more exposed to road grime, debris from other vehicles, etc. If the radiator develops a hole from corrosion or other damage, coolant may leak out.

Repair Costs

Replacing a leaky radiator clamp can cost just $15 if you do it yourself.

For small hairline cracks, radiator leak-stop products work great and cost less than $50. However, if soldering is required or the radiator needs to be replaced, expect to spend $1,000 to $1,500 or more.

Faulty Water Pump

Antifreeze can also leak due to problems with the water pump, a belt-driven device that circulates coolant through the system. If coolant is low, contaminated, or the belt has an issue, the pump can overheat and cause the gaskets and seals to leak.

Repair Costs

Estimates from RepairPal and Kelley Blue Book show water pump replacement costs range from $400 to $900.

If the timing belt is the issue, costs are slightly less at $367 to $756. Replacing the gaskets and seals is possible, but it’s often more feasible to just swap out the pump.

Worn Radiator Cap

Yes, even something as simple as a damaged or improperly torqued radiator cap can lead to coolant leaking from your car. With time, it’s also possible the cap’s seals dry out and crack, allowing pressurized antifreeze to leak out.

Repair Costs

How much is a coolant leak repair stemming from a leaky radiator cap? If the cap just needs tightening, repairs may cost nothing.

However, if the top needs to be substituted, anticipate spending less than $50 on a fresh one at an auto parts shop.

Cracked Expansion Tank

An expansion tank, or coolant reservoir, is essentially a plastic container holding the engine’s antifreeze.

It’s located beside the engine and connects to the radiator by a rubber hose. If the tank develops a crack or the connecting hose loosens or breaks, coolant will leak from under your car.

Repair Costs

Replacing an expansion tank typically costs between $400 to $450, according to my experience, which includes roughly $60 to $80 in labor costs.

If the tank is fine but the hose needs replaced, pricing ranges from $150 to $450 or more. You can also perform these repairs yourself to reduce overall costs.

Blown Head Gasket

The head gasket is what seals the connection between your car’s engine block and the cylinder head so that antifreeze can pass between.

Head gaskets usually last the life of an engine but can dry out and crack if the motor continually overheats, allowing coolant to leak out.

Repair Costs

Repairing the head gasket is costly because it requires a significant amount of time.

I estimate that the average cost is around $1800 to $2200. Of this, roughly $1100 to $1400 goes towards labor. For small cracks, you may also consider a specialty head gasket sealer for $50 to $100.

Minimize Repair Costs By Addressing Coolant Leaks Promptly

So, are coolant leaks expensive to fix?

Most coolant leaks cost less than $500 to repair if handled promptly. However, if a loose radiator cap or faulty water pump is ignored for too long, the engine will run out and possibly blow the head gasket or worse.

The main thing is to stay watchful for signs of a coolant leak, and if you notice something, address it. Some of the most apparent symptoms include a puddle of liquid under your car, engine overheating, or white smoke coming from the exhaust.

For a step-by-step guide on how to track a fluid leak, check out this video from YouTube’s 4DIYers.

Some repairs can be done at home, like a bad hose clamp or even a cracked expansion tank.

But other repairs are more complex and best left to professionals, like a damaged radiator or blown head gasket.