Tool Q&A

Questions on the selection, use and safety of hand tools may seem like they warrant no-brainer answers, you'd be amazed at the amount of unsafe and improper use of hand tools that goes on every day. In fact, the Consumer Product Safety Commission estimates that emergency treatments for injuries due to the misuse of hand tools amounts to around 150,000 each year. If you're an entry-level tech, the following information will help you get started on the right foot. If you're an experienced tech or shop owner, this might be a good opportunity to learn the errors of your ways and get back to basics.

Q. We recently hired a new tech and want to get him started on the right path about proper tool use in the shop. Where can I turn?

A. You can always refer to the Hand Tool Institute at www.hti.org for good basic information related to use and safety. As an example, the Institute provides basic guidance on proper wrench usage such as always pull on a wrench, never push. Don’t use extensions such as a pipe for added leverage and never use sockets intended for hand use. You can also ask your tool reps for any information they may have available.

Q. What’s the best type of torque wrench for my shop?

A. Although there are subtle variations, torque wrenches fall into three main categories: bar style, dial type and micrometer style. The right wrench depends upon the type of work you do, the types and range of torque specifications you’ll most often encounter, and, to some extent, personal preference. Since most shops work on a wide range of applications with different torque requirements, it’s likely that the best solution will come in the form of several torque wrenches. 

Q. Does a torque wrench require any special type of care or maintenance?

A. There are several things to keep in mind when it comes to the care and feeding of a torque wrench. First, you should restrict use to final tightening only; never use a torque wrench for disassembly like you would a breaker bar. Next, when tightening, support the head of the torque wrench with your other hand (the hand not doing the pulling) to maintain the proper pulling angle and contact with the fastener. When finished with an adjustable torque wrench, position its torque setting at its lowest reading before putting the tool away. Otherwise, the accuracy may be affected. Finally, torque wrenches are delicate instruments and need to be calibrated at least once a year — more often if dropped or used in a production environment.

Q. One of the techs in my shop questions whether it’s worth the time to use a torque wrench on fasteners. His theory is that there’s a large margin of error on torque anyway, so why bother?

A. Although tightening fasteners to their specific value has always been critical, now it’s crucial. When tightened, fasteners stretch ever so slightly to provide a clamping load on their related parts. With advanced materials and torque-to-yield (sometimes called “stretch”) bolts, this is especially so. In many cases, these types of bolts must be replaced after being tightened to specifications and cannot be reused.

Q. We install dozens of sets of tires every day. Tightening lug nuts to specifications is important, but we wish there was a faster way to do the job. Any thoughts?

A. Your shop sounds like it would be the perfect environment for torque sticks or wheel torque extensions. These carefully calibrated extensions and sockets apply a rated amount of torque and then begin to slip. There’s no need to change torque settings for different applications. You simply grab a different torque stick for a different size and tightening requirement. Torque sticks come in numerous drive and socket sizes and are color-coded for quick identification. There are even some torque sticks available for special vehicle wheels.

Q. Do I have to compensate the setting on a torque wrench when using extensions on the drive end?

A. It depends. Adding an extension on the vertical axis of rotation doesn’t require any compensation. An example would be adding, say, a 4" extension between the torque wrench drive end and the socket. Since this arrangement doesn’t increase the overall length of the torque wrench, it doesn’t change the effective lever created over the span of the torque wrench’s length. Adding anything to the drive end that does change the effective length (horizontal axis), however, requires compensation. For instance, let’s say you need to torque a fastener with a crow’s foot wrench. You would need to set the torque wrench to a lower setting than specs call for since the overall length would provide more effective leverage on the fastener end. The amount of compensation depends on the length of the wrench or socket attached to the drive end.

Q. We use different pullers regularly for removing gears and bearings among other things. What can I do to ensure safe usage?

A. First, always wear safety glasses. Make sure that you’re using a puller with the right size and capacity for the job at hand. Using too small a puller can result in injuries or damage to parts. Prior to using a puller, apply machine oil to the puller’s pressure screw to reduce friction and wear. When turning the pressure screw, use only hand tools, not power tools. For stubborn removal tasks, you can shock the item being removed by striking the pressure screw with a suitable hammer. During the pulling process, continuously monitor the puller to ensure that pulling jaws, draw bolts and the pressure screw remain in alignment. If necessary, stop and make the proper adjustments before continuing.

Q. Most service information requires a dial indicator to make run-out measurements on disc-brake rotors. Are there other places I can use this tool to stretch my tool investment a little further?

A. A dial indicator can be used to check for lash between gears, end play on crankshafts and camshafts in engines, flywheel run-out, wear in bushings and bearings and a whole lot more. If you need to take any of these sorts of measurements, your shop shouldn’t be without a dial indicator.

Q. On some vehicles, diagnosing driveline vibrations requires checking the driveshaft angle. To date, we’ve been making estimates with a protractor, but isn’t there a more precise tool for more exacting measurements?

A. Yes, you can do this much more accurately with a magnetic angle gauge. Simply affix the gauge to the driveshaft with the magnet and then read the gauge to determine the angle for comparison to specifications.

Q. Rear-disc-brake service has been a hassle for us because we have problems retracting the calipers during pad replacement. Because of this we sometimes install “loaded calipers” with the pads already installed to get around this issue. Is there a special tool for this?

A. Most rear-disc-brake calipers use a mechanical arrangement to apply the parking brake, in addition to the hydraulic piston that applies the pads when the regular brakes are activated. Over time and use, the parking brake mechanism moves the caliper piston further out. When replacing pads, the piston has to be rotated back into the caliper so there’s sufficient clearance to install the new pads. This can be done with a rear-caliper tool, which has pins that engage in the caliper piston. The tool then rotates the caliper piston back into the caliper housing. There are rear-caliper tools available for specific makes, and also sets that work on many popular makes and models. To be sure, always consult service information for what’s required.

Q. We need to replace a timing belt on a Volkswagen 2002 1.9L diesel engine. Do we need any special tools for this?

A. Yes, you will need several special tools to ensure that the belt is installed with the proper mechanical timing established. First, you will need a crank-lock tool to ensure that the crankshaft stays at TDC for the No. 1 cylinder. Next, you will need a cam-lock tool to make sure that the camshaft is in the valves closed position for No. 1 cylinder. You will also need a special injection pump-lock pin tool to confirm that the pump is set to base timing. Finally, an engine turning tool is also required for holding and turning the camshaft.

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