Before delving into the topic of Chevy 350 head gaskets, it is crucial to understand what a head gasket is and its role in an engine.
For those who are unfamiliar with head gaskets, they are typically dark gray with a red border and sit on top of the inline-four engine block. Once installed, the four large holes in the gasket align with the cylinders.
The primary function of head gaskets is to seal the combustion gasses within the cylinders and prevent any leakage of coolant or engine oil into the cylinders. A faulty head gasket can result in poor engine performance and overheating.
In a water-cooled internal combustion engine, three fluids pass through the head gasket between the engine block and the gasket itself: combustion gasses in the cylinder, water-based coolant in the coolant passages, and lubricating oil in the oil galleries.
By understanding the purpose and function of a head gasket, you can better comprehend the importance of maintaining and replacing it when necessary.
Chevy 350 Head Identification
Identifying Chevy 350 heads is a straightforward task due to the distinctive casting shapes found on the ends of the cylinder heads. While these casting marks cannot provide specific information about the cylinder heads, they can assist in distinguishing a performance head from a non-performance one.
Chevy 350 Head Gasket Replacement Process
The Chevy 350 is one of Chevrolet’s most popular small-block engines. Despite its reputation for durability, the engine is not immune to problems.
One common issue is a blown cylinder head gasket, which can be caused by overheating, a significant loss of power, and the harmful mixing of antifreeze and engine oil.
Although replacing a head gasket may seem daunting, the process is easier on the Chevy 350 than on many other engine types.
You can easily replace your Chevy 350 head gasket by following the straightforward procedure below.
STEP 1
To begin, remove the carburetor and distributor from the top of the intake manifold; start by locating the four nuts that attach the carburetor to the manifold. Each nut is positioned at the base of each corner of the carburetor, and you will need to remove all four nuts with a wrench. Once you have removed the nuts, carefully lift the carburetor away from the intake manifold.
Next, locate the single bolt that holds the distributor in place on the intake manifold. Remove the nut securing the distributor and gently pull the distributor away from the manifold to remove it.
STEP 2
Next, it is necessary to drain the coolant from the radiator and disconnect the upper radiator hose from the intake manifold. To do this, you can start by loosening all the bolts on the bottom of the radiator on the driver’s side to allow the coolant to drain.
The upper radiator hose is typically connected to the front of the intake manifold with a hose clamp with a single screw. To disconnect it, loosen the screw on the clamp and pull the hose away from the intake manifold.
STEP 3
Follow these steps to remove the intake, exhaust manifolds, and valve cover.
- The intake manifold is held in place with four bolts on each side. Remove the bolts and lift the manifold off the engine.
- The exhaust manifold is connected to the cylinder head with six bolts.
- Use a wrench to remove these bolts and pull the manifold away from the engine.
- The valve cover with bolts is attached to the cylinder head.
- Remove the bolts and lift the cover off the cylinder head.
STEP 4
Next, take off the eight rocker arms. Find the nuts in the middle of each rocker’s arm and take them off until you can twist the tip of each rocker’s arm from the top of its pushrod. Next, remove the eight pushrods from the engine. After that, remove the bolts that hold the cylinder head in place and lift it off the engine. Finally, loosen the old cylinder head gasket.
STEP 5
Lower the cylinder head onto the gasket’s mating surface. Avoid applying any gasket sealer to either side of the head gasket. Install all the cylinder head bolts and tighten them gradually to ensure even gasket seating. Next, slide the pushrods through the cylinder head and position the tip of each rocker’s arm over its pushrod before tightening the rocker arm bolts.
STEP 6
The valve cover, exhaust manifold, and intake manifold must be installed to proceed. Firstly, a new gasket must be used to establish the valve cover. To do this, both sides of the gasket must be coated with a gasket sealer. Then, position the gasket along the lip of the lid and lower the cover onto the cylinder head. Once the cover is in place, the valve cover’s four bolts can be installed and tightened.
A new gasket must also be used for the exhaust manifold, but the gasket sealer must be fresh. Bolt the exhaust manifold to the cylinder head using the new gasket. Four gaskets must be used and coated with gasket sealer before placement onto the engine.
Lastly, before lowering the intake manifold onto the gaskets and installing the manifold’s retaining bolts, the coated gaskets must be placed onto the engine.
STEP 7
To complete the process, connect the upper radiator hose to the intake manifold and refill the radiator with antifreeze. Then, carefully insert the distributor through the intake manifold and secure it with its single retaining bolt.
Next, position the carburetor on the engine and securely fasten the four retaining nuts.
It is crucial to seek professional guidance or assistance if you are unsure how to perform these steps correctly.
Chevy 350 Head Replacement Cost
Replacing the head gasket in a 5.7L Chevy 350 engine is relatively expensive, with an average cost ranging from $1200 to $1300. However, prices may vary depending on location and the vehicle the engine is used in, such as SUVs, pickup trucks, or sports cars.
It is highly recommended to seek the advice of a professional mechanic before attempting to replace the head gasket yourself or to have a mechanic perform the repair to ensure that no further or severe damage is caused to the engine during the gasket replacement process.
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