How to Replace a Cylinder Head Gasket

  • 4-8 hours
  • Advanced
  • 125-250
What You'll Need
New head gasket
Torque wrench
Pry bar
Intake manifold gasket
Valve cover gasket
Exhaust manifold gasket
Gasket sealer

The cylinder head gasket performs a vital function in the engine. It keeps coolant and oil from entering the combustion chamber and contaminating it. If it doesn’t do its job properly, your engine won’t function well and will run hot and eventually fail. Garages charge a great deal to replace a cylinder head gasket. It’s a complex repair and not recommended for novices, but it’s one you can still do yourself if you have enough mechanical experience.

Step 1 - Distributor

To remove the cylinder head gasket you’ll need to take out the distributor, if it’s positioned by the intake manifold. You’ll see that there’s only one bolt holding it in place. Use your wrench to remove it and take out the distributor.

Step 2 - Manifolds

Drain coolant before proceeding. You’re now at the intake manifold. Take out the bolts that hold it in place and then remove the manifold. You might need to pry it off using a pry bar. The exhaust manifold is on the side of the cylinder head. You’ll need to unbolt it and remove it. Both manifolds have gaskets. Use a scrape to remove any materials and clean the metal.

Step 3 - Cylinder Head

The valve cover sits on top of the cylinder head. You’ll need to take it out by removing the bolts. Now you’ll see the rocker arms, each held in place by a bolt. Remove these and take out the rocker arms and pushrods. This gives you access to the cylinder head itself. Loosen the bolts until you can take them out, then remove the cylinder head.

Peel off the cylinder head gasket. You’ll need to use the scraper to clean both the cylinder head and the engine block. Once both surface are fully clean, put the new gasket in place on the block, resting on the bolts. Make certain it’s the right side up and facing in the proper direction.

Put the cylinder head back on. There’s a set order for tightening the bolts, and you’ll need to consult your service manual for this. Use your torque wrench, taking time to be able to have each bolt at the correct pressure.

Step 4 - Replacing Parts

With the new cylinder head gasket in place, you need to put all the parts back in the engine. Begin with returning the pushrods to their proper positions, and then the rocker arms, tightening the bolt that attaches each one. Again, you’ll need to use your torque wrench for the correct pressure. Reattach the valve cover, replacing the old gasket. Use gasket sealer for this.

The exhaust manifold will also need a new gasket, although you should not use gasket sealer here. When you come to the intake manifold you will need to use gasket sealer to apply the new seal. Complete the replacement of the cylinder head gasket by returning the distributor to its proper place and bolting it down. Refill with coolant.