How To Use A Torque Wrench

The perfect tool to help with auto repair and other DIY maintenance requirements, torque wrenches are great as long as you know how to use them properly. From precise bolt and nut tightening, you will find that wrenches rise to this occasion best and help tighten loads so they will not loosen, stretch, or break.

Applications torque wrenches come ready to face

• Rod bolt connections
• Camshaft timing gear bolts
• Critical vehicle fastenings
• Engine cylinder head bolt tightening
• Flywheel bolts
• Manifold bolts for exhaust and intake
• Lug nuts
• Ball joint studs
• Bolts for main bearing caps
• Bolts for crankshaft pulleys
• Axle nuts

When you deal with the amount of torque that needs to be applied to a nut or bolt, you understand it to mean the amount of force you need to apply to get the job done. The wrench length and the force you need to apply on the handle go hand in hand (that is how we even got the equation: torque = force x length).

Useful conversion factors for torque wrenches

• One foot pound = 12 inch pounds.
• One foot pound = 1.3558 Nm
• One inch-pound = 0.1129 Nm
• One Newton Meter = 0.7375 ft.-lbs.

Performing torque corrections

Corrections are crucial technical steps used to achieve the most accurate readings. It boils down to using a torque wrench as it should be used.

• You hold the handle grip and either pull or push on that part of the handle alone. Anything else and you are looking at a skewed angle, which will result in a weak technique.
• The previous point is especially true for handles that have pivot points. The load must be balanced over the pivot point, and you need to grip the handle accordingly.
• If you plan to use socket and torque wrenches interchangeably, know that they make a good pair. While the torque reading will remain unchanged despite the use of an extension, it does not change the rule that the extension has to be maintained straight (parallel) to the fastener being tightened.
• Suppose instead you are using your torque wrench with a crow foot open end wrench, you need to position the latter in such a way that it is at a 90-degree angle to the handle. With this move, you keep leverage changes to a minimum and not have it affect your torque wrench reading’s accuracy.
• In keeping with the previous point, positioning the crow foot and maintaining it parallel to the handle will marginally extend the tool’s length and help increase leverage just a bit.
• You actually increase torque amount by 4-5% this way; depending on tool length. This means you need to reduce how much torque you personally apply by 4-5%.

Useful Videos

You can watch this 3 videos to learn how to use torque wrench: Video from ChrisFix:

Video from CarsNToys:

Video from Paul Foster:

Conclusion

There really is not much to using torque wrenches. Some would even say it is all common sense, how you apply force and when so the right kinds of tightening and fastening are achieved with little to no hassle; though you can certainly expect a steady quantity of perspiration.