Using a torque wrench to loosen bolts carries several risks, primarily related to over-torquing in reverse, damaging the wrench, or stripping the bolt head. While designed for precise tightening, their use in loosening can lead to unintended consequences if not handled with care.

Risks of Using a Torque Wrench for Loosening Bolts

Torque wrenches are indispensable tools for ensuring fasteners are tightened to a specific pre-determined tension. This precision is vital in many applications, from automotive repair to aerospace engineering, where over or under-tightening can have serious consequences. However, many people wonder if they can also be used for loosening bolts. While technically possible, using a torque wrench for loosening fasteners introduces several potential risks that users should be aware of.

Can You Use a Torque Wrench to Loosen Bolts?

Yes, you can use a torque wrench to loosen bolts, but it’s generally not recommended for several key reasons. The primary function of a torque wrench is to apply a specific amount of rotational force. When loosening, you’re essentially applying force in the opposite direction. This can lead to issues if the wrench isn’t designed for this kind of stress or if the bolt is seized.

Potential Dangers and Drawbacks

The risks associated with using a torque wrench for loosening bolts are varied and can impact both the tool and the fastener. Understanding these potential pitfalls can help you decide when it’s appropriate and how to mitigate risks.

Damaging the Torque Wrench

One of the most significant risks is damaging the internal mechanism of the torque wrench. These tools are calibrated for precise tightening. Applying a strong loosening force, especially on a stubborn bolt, can put excessive stress on the delicate components inside. This can lead to a loss of accuracy and render the wrench unreliable for future tightening applications.

• Over-stressing the spring mechanism: The spring that dictates the torque setting can be over-extended or damaged by a forceful counter-clockwise turn.
• Internal component failure: Gears and other internal parts are not designed to withstand the sudden, high forces often required for loosening seized bolts.

Stripping Bolt Heads or Threads

When a bolt is difficult to loosen, the temptation is to apply more force. Using a torque wrench for this can easily lead to stripping the bolt head. This means the tool (whether it’s a socket or wrench) can no longer grip the bolt, making removal extremely difficult, if not impossible, without specialized tools. Furthermore, excessive force can damage the threads on the bolt or within the mating component.

• Rounded bolt heads: The corners of the bolt head can become rounded, preventing any standard tool from getting a grip.
• Thread damage: Forcing a stuck bolt can shear or deform the threads, requiring more extensive repairs.

Over-Torquing in Reverse

While less common, it’s possible to over-torque a bolt in the loosening direction, especially with click-type torque wrenches. If you’re not paying close attention or if the wrench malfunctions, you might apply more force than intended. This can lead to unexpected breakages or damage to the components being disassembled.

Inaccurate Readings

Torque wrenches are calibrated for applying force in one direction (usually clockwise). Using them in reverse may result in inaccurate readings, if any reading at all. This defeats the purpose of using a precision tool and could lead to misjudgments about the force being applied.

When Might It Be Acceptable (with Caution)?

In some very specific scenarios, using a torque wrench for loosening might be considered, but only with extreme caution and when other options are limited. This typically applies to situations where you need to break a fastener loose gently to avoid damaging a sensitive component, and you have a good understanding of the expected torque range.

For example, if you know a bolt was torqued to a relatively low setting and you want to ensure you don’t exceed that limit significantly when loosening, a torque wrench might be used. However, a standard breaker bar or ratchet is usually the more appropriate tool for initial loosening.

Alternative Tools for Loosening Bolts

For most loosening tasks, especially those involving potentially seized fasteners, dedicated tools are far safer and more effective.

• Breaker Bar: This is a long, non-ratcheting bar that provides excellent leverage for breaking loose stubborn bolts. It allows for controlled, steady force application.
• Ratchet Wrench: A standard ratchet is designed for efficient tightening and loosening and is generally more robust than a torque wrench for initial force application.
• Impact Wrench: For very stubborn bolts, an impact wrench delivers rapid rotational impacts, which can be highly effective at breaking them free without applying excessive steady torque.

Best Practices for Using Torque Wrenches

To maintain the integrity and accuracy of your torque wrench, always follow these best practices:

• Use for Tightening Only: The safest and most effective use of a torque wrench is for applying precise torque during the tightening process.
• Store at Lowest Setting: After use, always return a click-type torque wrench to its lowest torque setting to relieve tension on the spring.
• Regular Calibration: Have your torque wrenches calibrated regularly to ensure their accuracy.
• Handle with Care: Avoid dropping or subjecting your torque wrench to impacts.

People Also Ask

### Can a torque wrench break a bolt loose?

Yes, a torque wrench can technically break a bolt loose by applying rotational force. However, it’s not its intended purpose. Applying significant force to loosen a bolt can damage the wrench’s calibration or internal components, and it may not provide enough leverage for very stubborn fasteners, risking stripping the bolt head.

### What happens if you use a torque wrench backwards?

Using a torque wrench backwards can lead to inaccurate readings or damage to the tool’s internal mechanism. While some wrenches might function in reverse, they are calibrated for forward motion, and applying significant loosening force can compromise their precision for future tightening tasks.

### Is it bad to use a breaker bar to loosen a bolt?

No, it is generally not bad to use a breaker bar to loosen a bolt. Breaker bars are specifically designed to provide high leverage for breaking loose stubborn fasteners. They offer controlled force application and are much less likely to damage the bolt head or the tool itself compared to using a torque wrench for loosening.

### How do you loosen a stuck bolt without stripping it?

To loosen a stuck bolt without stripping it, start with penetrating oil and allow it time to work. Use a six-point socket for maximum grip, and apply steady, even pressure with a breaker bar. If necessary, a few sharp taps with a hammer on the end of the breaker bar can help shock the threads loose.

Conclusion

While the temptation to use a torque wrench for loosening bolts might arise, the risks outweigh the benefits in most situations. Its precision is designed for tightening, and using it for loosening can lead to costly damage to the tool, the fastener, or surrounding components. Always opt for the right tool for the job, such as a breaker bar or ratchet