Have you ever dropped a nut or a bolt into an open intake manifold? Or dropped a fastener and watched it disappear into a crevice in the engine compartment? Or tried to find a wiring connector, plug or fastener by feel on the backside of an instrument cluster up under the dash? These are all situations where tools like a mirror, magnet and/or pickup tool can come in handy.
In today’s cramped engine compartments, elbowroom is at a premium. The engine and its accessories are usually packaged very tightly so many fasteners, plugs and wiring connectors are buried out of sight and can be very difficult to reach. Many of these things have to be located by feel, and changed using your fingertips.
That’s where a mirror can help. If you can see a fastener, you can usually tell what kind of tool you’re going to need to get it loose. Sometimes the opening on a Torx screw feels very much like an Allen head screw or even a Phillips screw. Being able to see a nut or a bolt also allows you to estimate what size wrench or socket you will need to get it loose (which saves a lot of back-and-forth time to your tool box). If you can see a sensor or other wiring connector, you can usually tell how it is held in place and what you’re going to have to do to release it.
Having a line of sight to a fastener, connector or other component that is normally obscured from view can also help you guide your tool to the right spot. That saves a lot of fumbling and fuming, and unnecessary profanity about the engineer who designed it that way.
Shop mirrors are relatively inexpensive (usually less than $10), and come in a variety of sizes and configurations. Some are round and some are long and narrow. Most have a swivel joint that allows the mirror to be twisted around in to almost any position. The handle may also extend for added length. A lighted mirror is always a plus. Some mirrors are now available with one or more little LED lights to shed light on what it is you are trying to see. Or you can use a separate battery-powered portable LED light with your mirror to improve your visibility.
The trick with using a mirror is getting it positioned so it allows you to see without blocking access to the fastener, connector or other part you are trying to reach. Using a mirror also requires the mental gymnastics of using reverse eye-hand coordination. The image you see in the glass is a reflected image, so everything is reversed 180 degrees, including lettering and numbering.
Another “must have” tool every technician needs (especially if they have butter fingers), is a magnetic pickup tool. Like mirrors, the magnets come in a variety of sizes and lengths. The magnetic head usually swivels, and the handle often extends so you can reach parts that have fallen into hard-to-reach places. The only problem with using a strong magnet to pick up a dropped fastener is that the magnet wants to stick to everything else that is steel. Consequently, it may take some patience to direct the tool to the exact spot where you want it to go. Also, a magnet will only pick up ferrous parts (steel or iron). It won’t pick up stainless steel fasteners (which are nonmagnetic), brass fasteners or plastic parts. For these kind of jobs, you also need a grabber tool.
A typical grabber tool has a long, flexible shaft so you can snake it almost anywhere. When you squeeze the handle or push the knob in on the end of the tool, the wire fingers at the other end of the tool extend like little fingers. When you release the handle or knob, the little fingers retract and hopefully grab onto and hold what you are trying to pick up or retrieve.
Grabber tools are also very inexpensive and can be used for a variety of jobs including grabbing and pulling wires through hard-to-reach openings up under the dash, to retrieve anything you might have dropped into an open intake manifold or cylinder head port, to retrieve nuts, bolts or drain plugs that have fallen into a catch pan full of antifreeze or oil (a magnet works well for this, too), to fish things out of a radiator end tank, cooling jacket or differential, etc.
If you have a stomach ailment, a doctor may use a flexible fiber optic scope to peer down your throat to view the inside of your esophagus and stomach. And if you have an issue at the other end of your digestive tract, the doctor can shove a scope in the other way to take a look. This same technology can also be used by technicians for doing visual diagnostics inside an engine or any other component that has an opening large enough to accept the business end of such a tool, which may range in size from a few millimeters in diameter up to 14 mm.
A fiber optic scope (sometimes called a borescope or a fiberscope) can be inserted through a spark plug opening to examine the inside of the combustion chamber and cylinder. Such a tool may allow you to see a hairline crack or a coolant leak. You might also see valve damage that is causing a loss of compression, or damage to a cylinder that may be affecting oil consumption. You can use the same tool to peer inside the crankcase to inspect the connecting rods, crankshaft and oil pump pickup tube, or to look inside a valve cover to inspect the rocker arms or the lobes on an overhead camshaft. You might also use it to check for chipped or broken gear teeth inside a transmission or differential. And if you can get it past the rollover restrictor inside the fuel tank filler neck, you can also inspect the inside of a fuel tank for rust or debris.
Fiber optic scopes can cost anywhere from several hundred dollars up to several thousand dollars. The scope typically provides its own light source, and displays the image picked up by the lens on a view screen. More expensive models can feed the image directly to a digital camera or a computer for viewing and recording. The optical fibers inside the shaft transmit the image from one end of the tool to the other. Some of the high-end tools have a miniature video camera on the end of the tool and do not use fiber optics to transmit the image.
On tools with flexible shafts (which are the most versatile), the shaft may be from one to four feet in length. Those with rigid shafts are usually shorter, ranging from one to two feet in length with a simple eye-piece viewer on the end.
In addition to seeing what’s going on inside an engine, another useful tool is a mechanic’s stethoscope. The type that technicians use typically has a long probe that allows you to listen to noises produced by various components. It’s a great tool for listening to the fuel injectors. You can also listen to the shaft bearings on alternators, water pumps, power steering pumps and A/C compressors, idler pulleys and automatic belt tensioners. It’s a handy tool for pinpointing valve noises, bad wheel and axle bearings, and for listening to solenoids to see if they are clicking or not. You can usually get a stethoscope for less than $50.