National 7109 Clutch Pilot Bearing

Overview of National 7109 Clutch Pilot Bearing

The National 7109 clutch pilot bearing is engineered for reliable performance in select Buick, Oldsmobile, and Pontiac models. Designed as a single row angular contact ball bearing, it ensures smooth clutch operation and precise alignment of the transmission input shaft.

• Single row angular contact design for efficient load handling
• Inner race bore diameter of 0.591 inches (15 mm)
• Outer race outside diameter of 1.378 inches (35 mm)
• Width of 0.354 inches (9 mm) for compact fitment
• Compatible with multiple Buick, Oldsmobile, and Pontiac vehicles

Technical Specifications and Design Features

The National 7109 clutch pilot bearing features a ball bearing design with a single row angular contact configuration, providing optimal radial and axial load support. The inner race bore measures 0.591 inches (15 mm) with a radius of 0.025 inches, while the outer race diameter is 1.378 inches (35 mm) with the same radius. Both inner and outer races have a width of 0.354 inches (9 mm), ensuring a precise fit within the transmission assembly. This bearing type A-1 from the Special series is engineered to maintain alignment between the engine crankshaft and transmission input shaft, reducing wear and vibration during clutch engagement.

Compatible Vehicles and Applications

This clutch pilot bearing is compatible with a range of classic and late-model vehicles, including Buick models such as Century, LeSabre, and Skylark; Oldsmobile models like Cutlass, Delta 88, and 98; and Pontiac models including Firebird, Grand Prix, and GTO. The National 7109 is suitable for use in transmissions requiring a 15 mm bore clutch pilot bearing, making it a reliable replacement part for maintaining clutch system integrity in these vehicles.

Common Issues Addressed by the National 7109 Bearing

• Eliminates clutch chatter caused by worn or damaged pilot bearings
• Prevents transmission input shaft misalignment
• Reduces premature wear on clutch components
• Minimizes vibration and noise during clutch engagement
• Supports smooth and consistent clutch operation

Installation Notes and Tips

When installing the National 7109 clutch pilot bearing, ensure the transmission input shaft and crankshaft pilot hole are clean and free of debris. Use appropriate tools to press the bearing evenly into place without applying excessive force that could damage the bearing races. Verify the bearing is fully seated and rotates smoothly before reassembling the clutch and transmission components. Proper lubrication and alignment during installation will extend the bearing's service life.

Quality Assurance and Warranty Information

National clutch pilot bearings are manufactured to meet industry standards for durability and performance. The 7109 bearing undergoes rigorous quality control to ensure dimensional accuracy and material integrity. While specific warranty terms may vary, National typically offers coverage against manufacturing defects, providing confidence in the product's reliability for Buick, Oldsmobile, and Pontiac applications.