How to Replace a Head Gasket on a Chevy 350


Replacing a head gasket on a Chevy 350 can be a daunting task, but it’s one that you can do with the right tools and knowledge. In this article, we will guide you through the process step-by-step, from gathering the necessary supplies to completing the job. We will also discuss common mistakes and how to avoid them, so you can have a successful outcome.


Before you start, it’s important to gather all the tools you’ll need for the job.

Some of the essential items include:

  • A socket wrench set

  • An adjustable wrench

  • A ratchet wrench

  • A torque wrench

  • A coolant flush kit

  • New head gaskets
  • New head bolts
  • Plastic gloves
  • Safety glasses
  • A bucket or container to catch coolant

You will also need a new timing chain and guides if the old ones are damaged. It’s recommended to take your vehicle to a professional mechanic if you don’t have experience with this type of work.


Step 1:

Drain the Coolant

The first step is to drain the coolant from the radiator. This will make it easier to access the head gaskets and bolts. You can do this by connecting a hose to the radiator drain plug and placing the other end in a bucket or container. Make sure the bucket is big enough to hold the entire radiator flush kit.

Step 2: Remove the Old Head Gaskets

Remove the old head gaskets by unscrewing the bolts that hold them in place. Use a socket wrench set and an adjustable wrench to make this process easier. You may also need a ratchet wrench if the bolts are stuck or corroded. Take your time and be careful not to damage any other components nearby.

Step 3: Check for Damage

Before installing the new gaskets, check the cylinder heads and block for any signs of damage. Look for cracks, warping, or holes in the aluminum. If you see any of these signs, it’s best to take your vehicle to a professional mechanic as this could be a more serious issue that requires additional repairs.

Step 4: Install the New Head Gaskets

Apply a small amount of coolant to the gasket surfaces and use an adjustable wrench to tighten the bolts in a star pattern, starting with the center bolt and working outward. Make sure you don’t over-tighten the bolts as this could damage the head gaskets or the head bolts.

Step 5: Replace the Head Bolts

Replace the old head bolts with new ones that are compatible with your Chevy 350. Use a torque wrench to tighten the bolts to the recommended specification, which is typically around 12-18 ft-lbs.

Step 6: Refill the Coolant

Once everything is tightened and secured, refill the radiator with the coolant flush kit. Check the hoses and belts for any leaks or damage before starting the engine.



What if I see water in my oil?

A: If you see water in your oil, it’s a sign that there may be a problem with the head gaskets or seals. It could also indicate that the timing chain is damaged or loose. Take your vehicle to a professional mechanic for further diagnosis and repair.