Honda B18 Cylinder Head Cam Journal Scoring Repair Using Undersize Bearings

Identifying Cam Journal Scoring on a Honda B18 cylinder head

Cam journal scoring on a Honda B18 cylinder head is a common issue that can lead to reduced engine performance and increased wear. This scoring occurs when the camshaft journals experience excessive friction, often caused by insufficient lubrication or contamination within the oil passages. Over time, this results in visible grooves or scratches along the bearing surfaces.

Regular inspection of the cam journals is essential for early detection. Signs such as unusual engine noises, decreased power output, or metal debris in the oil may indicate underlying scoring problems. Removing the cylinder head and visually checking the cam journals can help confirm the extent of the damage before proceeding with repairs.

Repairing Cam Journal Scoring Using Undersize Bearings

One effective method to repair cam journal scoring is by using undersize bearings. These bearings are designed with slightly reduced inner diameters to compensate for the worn or scored cam journals, restoring proper clearance and ensuring smooth rotation. This approach avoids the need for more expensive machining or replacement of the entire cylinder head.

The repair process begins with precise measurement of the cam journal diameters and the scored areas. Based on these measurements, appropriate undersize bearings are selected to achieve optimal fitment. installation requires careful alignment and torque settings to maintain oil flow and prevent further damage during operation.

After installing the undersize bearings, it is crucial to perform a thorough break-in procedure. This helps seat the new bearings correctly and ensures consistent lubrication. Regular maintenance and monitoring following the repair will prolong the life of the cylinder head and camshaft assembly.