About the 420a Engine
The 420a engine is a four-cylinder, 2.0-liter engine that was produced by Chrysler Corporation and Mitsubishi Motors. It was commonly used in various models, including the Dodge Neon, Plymouth Neon, and Mitsubishi Eclipse. The 420a engine was known for its performance and reliability, making it a popular choice among car enthusiasts and everyday drivers alike. One crucial aspect of maintaining this engine’s performance is ensuring the proper torque specifications for the head bolts. In this article, we will provide you with the recommended head bolt torque specs for the 420a engine.
420a Head Bolt Torque Specifications
To ensure the proper sealing and integrity of the engine’s cylinder head, it is essential to tighten the head bolts to the correct torque specifications. The table below provides the recommended torque values for the head bolts of the 420a engine, expressed in foot-pounds (ft. lbs.) and Newton-meters (Nm).
| Head Bolt | Torque Specifications (ft. lbs.) | Torque Specifications (Nm) |
|---|---|---|
| 1 | 30-35 | 41-47 |
| 2 | 30-35 | 41-47 |
| 3 | 30-35 | 41-47 |
| 4 | 30-35 | 41-47 |
| 5 | 30-35 | 41-47 |
| 6 | 30-35 | 41-47 |
| 7 | 30-35 | 41-47 |
| 8 | 30-35 | 41-47 |
Steps to Torque the Head Bolts
To properly torque the head bolts of the 420a engine, follow these steps:
1. Start by cleaning the threads of the head bolts and the bolt holes in the engine block to ensure proper engagement and accurate torque readings.
2. Apply a small amount of engine oil or assembly lubricant to the threads and the washer face of each head bolt. This will help reduce friction and ensure consistent torque readings.
3. Begin tightening the head bolts in a specific sequence. The recommended sequence is typically provided in the engine’s service manual. Tighten each bolt in small increments, following the specified torque specifications.
4. Once all the head bolts have been initially torqued, go back and repeat the sequence, increasing the torque to the final specifications. This process is known as the torque-to-yield method and helps ensure proper clamping force.
5. Finally, perform a final pass on all the head bolts, following the specified torque specifications one last time to ensure they are properly tightened.
By following these steps and using the recommended torque specifications, you can ensure that the head bolts of your 420a engine are tightened correctly, providing a secure seal and maintaining the engine’s performance and reliability.
Conclusion
Properly torquing the head bolts of the 420a engine is crucial for maintaining its performance and preventing any potential issues. By following the recommended torque specifications and using the correct tightening sequence, you can ensure that the head bolts are properly secured, providing a reliable seal for the engine’s cylinder head. Regular maintenance and attention to torque specifications will help keep your 420a engine running smoothly for years to come.