The cylinder head gasket is a crucial engine component that seals the cylinders and allows them to maintain compression and hold coolant and oil. Over time, this gasket can fail, leading to some serious issues. In such cases, replacing the gasket with a high-quality one like Ajusa cylinder head gaskets can help ensure the engine runs smoothly and efficiently. Let’s take a closer look at cylinder head gaskets and what you need to know about them.

cylinder head gaskets suppliers

What Does a Cylinder Head Gasket Do?

Sitting between the engine block and cylinder head, the head gasket has some vital jobs:

Prevent Leaks

The gasket creates a tight seal to prevent combustion gases and coolant from leaking out. Leaks can lead to overheating, poor performance, and damage.

Withstand Heat and Pressure

Inside those cylinders, temperatures reach over 2000°F. The gasket has to withstand extreme heat as well as up to 2000 psi of pressure. Quality materials and design prevent it from being blown out.

Allow Coolant and Oil Flow

While sealing cylinders, the gasket must also allow coolant and oil to flow through to their required areas. Proper flow is critical to preventing hot spots and lubrication issues.

Why Do Head Gaskets Fail?

There are a few reasons cylinder head gaskets eventually give out:

High Mileage and Age

As engines rack up miles, gaskets experience more and more punishment from heat cycles, pressure spikes, and vibration and can eventually fatigue or get crushed.

Improper Torque

If the head wasn’t torqued down to spec, the gasket may leak from inadequate load and clamping force. This can happen after repairs if mechanics are not careful.


Sustained overheating can dry out, crack or burn a head gasket. Warped heads from extreme heat can also prevent proper sealing.

Chemical Deterioration

Coolant mixtures with chlorine or chlorides can deteriorate rubber gaskets over time. Using the manufacturer’s recommended coolant is best.

Spot Signs of Head Gasket Failure

Watch for these symptoms if you suspect a failing head gasket:

  • White exhaust smoke or coolant loss
  • Oil contamination of coolant or vice versa
  • Poor engine performance
  • Overheating issues
  • Bubbling in the radiator and overflow tank

Get the Head Gaskets Replaced

While diagnosing bad head gaskets yourself is possible, replacement should be left to professional mechanics. The job requires

  • Methodically disassembling components for access
  • Degreasing and cleaning surfaces
  • Checking the straightness of deck surfaces
  • Selecting proper replacement gaskets
  • Precisely torquing the new gasket to spec

This is crucial and best left to those with experience. Expect labor costs to easily exceed $1000 but it’s less than the cost of a damaged engine.

Prevent Repeat Head Gasket Failures

Once you have new head gaskets installed, you’ll want them to last. Here are some tips:

  • Maintain proper coolant mixture and change intervals
  • Watch coolant levels and temperature gauges for overheating
  • Address any leaks or oil consumption issues
  • Follow service intervals for tune ups and preventative maintenance
  • Consider adding Coolant System Additives to help seal small leaks


What is the average cost to replace a head gasket?

  • The average cost for cylinder head gasket replacement is $1,200-$1,500 including parts and labor. The job typically takes 6-8 hours.

How urgent is a head gasket leak?

  • Small leaks can be monitored but should be addressed quickly before causing engine damage. Severe leaks requiring frequent coolant top-offs should be repaired immediately.

Can I drive with a blown head gasket?

  • It’s not recommended to drive with a blown head gasket. This can allow coolant and oil to mix, leading to overheating, hydrolock, and engine components failing.

Do you have to replace head bolts when changing the gasket?

  • Many mechanics recommend replacing head bolts as a precaution when changing head gaskets. Reusing bolts risks improper torque or stretching.

Can head gasket sealers permanently fix a leaking gasket?

  • Sealers can temporarily swell gaskets and stop small leaks but don’t offer permanent repairs. The underlying issue of a failing gasket remains, needing replacement.

In summary, the cylinder head gasket is integral to engine operation and sealing the cylinders properly. When it eventually fails from age, overheating, or damage, critical leaks can occur. Watch for symptoms of failure, avoid driving once blown, and have the gaskets promptly replaced by an experienced mechanic. With a quality job and preventative maintenance, your new head gaskets should last for years to come.