Installing Cam Bearings in an SBC: A Guide to Precision and Performance

Introduction

Installing cam bearings in a small block Chevrolet (SBC) engine is a critical step in building a high-performance or reliable powerplant. Cam bearings provide support and alignment for the camshaft, ensuring proper valve timing and minimizing friction. This guide will provide a comprehensive overview of the process, including the tools, techniques, and best practices for achieving optimal results.

Tools and Materials

To install cam bearings in an SBC, you will need the following tools and materials:

• Cam bearing installer
• Cam bearing removal tool
• Dial indicator and magnetic base
• Set of cam bearings
• Engine block
• Oil and assembly lube

Preparing the Engine Block

1. Before installing the cam bearings, the engine block must be thoroughly cleaned to remove any dirt or debris.
2. Use a solvent and a clean rag to wipe down the bearing bores in the block.
3. Check the cam bearing bores for any signs of damage, such as scratches or gouges. If any damage is found, the block may need to be repaired or replaced.

Installing the Cam Bearings

1. Apply a small amount of assembly lube to the outside of the cam bearing.
2. Place the cam bearing into the bearing bore and use the cam bearing installer to press it into place.
3. Ensure that the bearing is fully seated and flush with the block surface.
4. Repeat this process for all four cam bearing bores.

Checking Cam Bearing Alignment

1. Once the cam bearings are installed, use a dial indicator and magnetic base to check the alignment of the bearing bores.
2. Rotate the crankshaft and measure the runout of the cam bearing bores.
3. The runout should be within 0.002 inches for optimal camshaft alignment and performance.

Troubleshooting Common Issues

1. If the cam bearings are not fully seated, they may not provide adequate support for the camshaft. This can lead to excessive wear or even camshaft failure.
2. If the cam bearing bores are not properly aligned, it can cause the camshaft to bind or walk out of position. This can lead to poor valve timing and reduced engine performance.
3. If the cam bearings are damaged, they may not be able to properly support the camshaft, leading to premature wear or failure.

Tips and Tricks

• Use a cam bearing installer specifically designed for SBC engines to ensure proper alignment.
• Apply a thin layer of assembly lube to the cam bearings to reduce friction during installation.
• Measure the cam bearing bores before and after installing the bearings to verify correct alignment.
• If the cam bearing bores need to be repaired, consult a qualified machinist for professional assistance.

Why Installing Cam Bearings Matters

Installing cam bearings in an SBC engine is essential for the following reasons:

1. Precision Alignment: Cam bearings ensure precise alignment of the camshaft, which is crucial for proper valve timing and engine performance.
2. Reduced Friction: Cam bearings minimize friction between the camshaft and the block, reducing wear and extending the life of both components.
3. Improved Durability: Properly installed cam bearings provide a solid foundation for the camshaft, reducing the risk of camshaft failure and premature engine wear.

Benefits of Proper Cam Bearing Installation

Properly installed cam bearings provide the following benefits:

1. Enhanced Engine Performance: Optimal camshaft alignment and reduced friction contribute to increased engine power and efficiency.
2. Extended Engine Life: Reduced wear and tear on the camshaft and block extends the lifespan of the engine and reduces maintenance costs.
3. Peace of Mind: Knowing that the cam bearings are installed correctly provides peace of mind and ensures the reliability of the rebuilt engine.

FAQs

1. What is the typical cost of installing cam bearings?
   - The cost of installing cam bearings varies depending on the complexity of the job and the location of the shop. On average, expect to pay between $150 and $300 for professional installation.

   

2. How often should cam bearings be replaced?
   - Cam bearings should be replaced during any major engine rebuild or if there are signs of excessive wear or damage.

   

3. Can I install cam bearings myself?
   - While it is possible to install cam bearings yourself, it is highly recommended to seek professional assistance if you are not experienced in engine rebuilds. Improper installation can lead to serious engine damage.

4. What are common symptoms of worn or damaged cam bearings?
   - Signs of worn or damaged cam bearings include excessive engine noise, reduced oil pressure, and poor engine performance.

5. What happens if cam bearings fail?
   - Cam bearing failure can lead to loss of oil pressure, camshaft seizure, and catastrophic engine damage.

6. Can cam bearing failure be prevented?
   - Proper installation, regular oil changes, and using high-quality oil can help prevent cam bearing failure.

7. What is the average lifespan of cam bearings?
   - With proper care and maintenance, cam bearings can typically last the lifetime of the engine.

   

Humorous Stories

1. A mechanic was installing cam bearings in an SBC engine when he accidentally dropped the bearing into the oil pan. He spent hours searching for it before realizing it was attached to the camshaft, which he had already installed.

2. A customer brought his SBC engine to a shop complaining of a strange noise. The mechanic listened to the engine and diagnosed the problem as loose cam bearings. To fix it, the mechanic removed the camshaft and replaced the bearings with new ones. When he started the engine, the noise was still there. The mechanic realized he had installed the cam bearings upside down.

3. A do-it-yourselfer was installing cam bearings in his SBC engine when he realized he had forgotten to remove the old bearings. He decided to install the new bearings over the old ones, thinking it would provide extra support. When he started the engine, it seized up immediately.

Conclusion

Installing cam bearings in an SBC engine is a critical part of building a high-performance or reliable powerplant. By following the steps outlined in this guide and using the right tools and techniques, you can ensure that your camshaft is properly supported and aligned, resulting in optimal engine performance, reduced wear, and extended engine life.

Additional Resources

• SBC Cam Bearing Installation Guide
• How to Replace Cam Bearings in a Small Block Chevy