National 710644 Engine Crankshaft Seal - Front

Overview of National 710644 Engine Crankshaft Seal

The National 710644 engine crankshaft seal is designed for reliable sealing performance in select Toyota vehicles. Engineered with a fluoro-elastomer material and a clockwise-spiral lip design, this oil seal helps maintain engine integrity by preventing oil leaks around the crankshaft.

• Inside diameter: 1.890 inches (48.000 mm)
• Outside diameter: 2.689 inches (68.300 mm)
• Thickness/width: 0.276 inches (7.000 mm)
• Material: durable fluoro-elastomer
• Helix type: clockwise-spiral lip design for effective sealing
• Compatible housing bore: 2.677 inches (68.000 mm)
• Part number: 710644, series 710600

Technical Details and Specifications

This National crankshaft seal (part number 710644) is constructed from fluoro-elastomer, a material known for its resistance to heat, oil, and chemicals, making it suitable for demanding engine environments. The seal features a clockwise-spiral lip design that enhances sealing efficiency by directing oil back into the engine, reducing leakage. With an inside diameter of 1.890 inches and an outside diameter of 2.689 inches, it fits precisely into the housing bore of 2.677 inches, ensuring a secure fit. The 0.276-inch thickness provides durability without compromising flexibility.

Compatible Toyota Models and Applications

This engine crankshaft seal is compatible with various Toyota models, including the 4Runner, Previa, T100, and Tacoma. It is specifically designed to meet the sealing requirements of these vehicles’ crankshaft assemblies, helping to maintain engine oil containment and prevent contamination.

Common Issues Addressed by the National 710644 Seal

• Prevents oil leaks around the crankshaft area
• Reduces risk of engine contamination from external debris
• Maintains proper oil pressure by sealing the crankshaft
• Minimizes wear on crankshaft bearings by retaining lubrication
• Helps avoid costly engine repairs due to oil loss

Installation Notes and Tips

When installing the National 710644 crankshaft seal, ensure the housing bore and shaft surfaces are clean and free of debris. Use appropriate tools to press the seal evenly into the bore without damaging the lip. Verify the seal orientation matches the clockwise-spiral lip design to optimize sealing performance. Lubricate the seal lip lightly with clean engine oil before installation to reduce initial wear.

Quality Assurance and Warranty

National’s 710644 crankshaft seal is manufactured to meet industry standards for durability and performance. The fluoro-elastomer material and precision design contribute to long service life under normal operating conditions. While specific warranty details may vary, National products typically come with a limited warranty against manufacturing defects, ensuring confidence in the part’s quality.