The Ultimate Guide to SBC Cam Bearing Installation

Introduction

Replacing cam bearings is a crucial step in rebuilding or modifying a small block Chevy (SBC) engine. These bearings support the camshaft and ensure its proper alignment and operation. Installing cam bearings correctly requires precision and attention to detail to prevent premature camshaft failure and costly engine damage.

Understanding SBC Cam Bearings

SBC cam bearings are precision-machined inserts that fit into the engine block's lifter bores. They provide a smooth, low-friction surface for the camshaft to rotate on. Cam bearings come in different sizes and thicknesses, depending on the specific camshaft and engine application.

Tools and Materials Required

Essential Tools:

• Cam bearing installer
• Dial indicator
• Feeler gauge
• Torque wrench
• Cam bearing removal tool (optional)

Materials:

• SBC cam bearings
• Engine block
• Engine oil

Preparation

1. Clean the Block:

• Thoroughly clean the engine block's lifter bores using a solvent and brush.
• Remove any dirt, oil, or debris that could interfere with the bearing installation.

2. Measure Bore Alignment:

• Use a dial indicator to check the alignment of the lifter bores.
• Ensure that the bores are within the manufacturer's specifications for concentricity and parallelism.

Cam Bearing Installation

1. Lubricate Bearings:

• Apply a thin layer of engine oil to the outer surface of the cam bearings.

2. Install Bearings:

• Hold the cam bearing installer firmly over the lifter bore.
• Align the bearing with the bore and carefully drive it into place using a hammer or press.

3. Check Bearing Depth:

• Use a feeler gauge to measure the depth of each cam bearing below the block's surface.
• The proper depth will vary depending on the camshaft and engine application.

Cam Bearing Removal

1. Access Lifter Bores:

• Remove the intake manifold and camshaft to access the lifter bores.

2. Use Removal Tool:

• Insert a cam bearing removal tool into the lifter bore.
• Engage the tool with the bearing and carefully pull it out.

3. Clean Bore:

• Clean the lifter bore thoroughly to remove any bearing debris.

Tips and Tricks

• Use a bearing installer: A専用 cam bearing installer is essential for proper bearing installation.
• Check bearing clearance: Use a dial indicator to ensure proper clearance between the camshaft and bearings.
• Apply thread sealant: Apply a small amount of thread sealant to the cam bearing bolt threads to prevent leaks.
• Tighten bolts evenly: Tighten the cam bearing bolts using a torque wrench in a crisscross pattern to ensure even clamping force.
• Run engine in: Once cam bearings are installed, run the engine at low RPM for a short period to allow the bearings to seat properly.

Troubleshooting

Common Issues:

• Bearing binding: This can occur if the bearings are not properly aligned or installed at the correct depth.
• Excessive bearing clearance: This can lead to camshaft wear and reduced engine performance.
• Oil leaks: Leaks can occur if the cam bearing bolts are not tightened properly or if the bearing bores are damaged.

FAQs

1. How often should cam bearings be replaced?

• Every time the camshaft is replaced or the engine is rebuilt.

2. What is the torque specification for cam bearing bolts?

• Varies depending on the engine application. Consult the manufacturer's specifications.

3. Can I reuse cam bearings?

• No, it is not recommended to reuse cam bearings.

4. Do I need to hone the lifter bores before installing new cam bearings?

• Only if the lifter bores are damaged or have excessive wear.

5. Can I install cam bearings without removing the camshaft?

• No, the camshaft must be removed to properly install cam bearings.

6. What are the symptoms of worn cam bearings?

• Noisy valvetrain, excessive oil consumption, decreased engine performance.

Call to Action

Properly installed cam bearings are critical for the longevity and performance of an SBC engine. By following the steps outlined in this guide, you can ensure a successful cam bearing installation and avoid costly engine damage. If you are not comfortable performing this task yourself, consult with a qualified mechanic.