See Figures 20 thru 28
In addition to basic tools, you'll find a number of small specialty tools that will make your life as a do-it-yourselfer much easier. A battery terminal puller (for top terminal batteries) costs only a few bucks, and will save you a lot of trouble when you remove your battery cables. A combination cable and terminal cleaner is also handy. A tire pressure gauge is an absolute must if you plan to get the most wear out of your tires. Buy a good one, since tire pressure is critical to tire life. An antifreeze hydrometer is necessary to keep an eye on the state of your coolant. Fig. 20 Side terminal battery cleaning tool
Fig. 21 Battery terminal puller
Fig. 22 Top battery terminal cleaning tool
Fig. 23 Tire pressure gauges top, and tread depth gauges bottom
Fig. 24 A hydrometer is necessary to check antifreeze protection
Fig. 25 Tools from specialty manufacturers such as Lisle and Cal-Van are designed to make your job easier. Here is an assortment of brake tools.
Fig. 26 Specialty sockets are required for many sensors and axle nuts. Acquire these as the job calls for it.
Fig. 27 Special pullers are required for various applications. Often these tools can be rented from a tool rental or auto parts store.
Fig. 28 Interior door handles and panels often require special clip removers
General Maintenance Tools
The list of general maintenance tools is practically endless, depending on the degree of your involvement. However, a basic list for the average do-it-yourself mechanic would include:
- An oil filter wrench,
- A grease gun,
- A container for draining oil,
- A suction gun,
- Battery terminal cleaners, and
- Many rags for cleaning up the inevitable mess.
Oil filter wrenches come in various types. The strap wrench is the most common and will handle most filters. A more sophisticated filter wrench combines a strap or band wrench with a ratchet drive. This type is useful when the filter is located in an out-of-the-way place. Many oil filters on front wheel drive vehicles, can only be removed with this type of wrench. The other types of filter wrenches are applied to the end of the oil filter, and both are designed for use with a ratchet drive.
A funnel is the best way to get oil from the bottle into the engine with a minimum of mess. Any other way will surely result in oil spilled on the engine, which will turn to smoke when the engine gets hot. Other types of fillers have flexible spouts for filling automatic transmissions and other hard-to-reach filler tubes.
A grease gun is also the only way to lubricate the vehicle's chassis. The grease gun comes in various sizes that accept cartridges of different kinds of grease and a variety of flexible and odd-shaped fittings to reach hard-to-get-at grease nipples.
A fluid suction gun is almost a necessity to add (or remove) oil from a differential. The filler plugs on differentials and manual transmissions are frequently in a spot that you cannot fill directly from the container. You will probably have to transfer the fluid from the container into a suction gun first. The fluid is also frequently heavy oil, which does not flow easily, which further complicates the problem. To remove fluid from a unit without a drain plug, a suction gun is invaluable.
Battery cleaning tools are inexpensive and make battery terminal cleaning easier and quicker. They generally come in two styles, one for top terminals and one for side terminals. The one for side terminals is nothing more than a miniature wire brush, which you can easily substitute. Fig. 29 Oil filter wrenches come in a number of styles. You will have to experiment to find the correct combination for your vehicle.
Fig. 30 Lubrication tools- suction gun, grease gun, and bearing packers
Fig. 31 This type of oil drain pan enables you to take your waste oil to a recycling station. Remember to drain the filter into the pan.
Tune-Up Tools
The word "tune-up" actually applies only to older vehicles, on which you can perform the traditional work associated with "tune-up"- spark plug replacement, ignition contact point replacement, dwell adjustment, ignition timing adjustment and carburetor idle and mixture adjustment.
For today's vehicles, engine performance maintenance is a more accurate term. Modern vehicles are equipped with electronic ignition (no points) and an on-board computer that automatically adjusts the ignition timing fuel mixture and idle speed. In fact, on modern computer-controlled vehicles, it's usually impossible to adjust these yourself:
If you plan to do your own engine performance maintenance, there are some specialized tools you are going to need. You'll need a round wire gauge to check and set the plug gap, a timing light (if your ignition timing is adjustable), a dwell-tach or just a tach (to set idle speed if it is adjustable). A compression gauge is also handy, though not necessary.
An important element in checking the overall condition of your engine is to check compression. This becomes increasingly more important on high mileage vehicles. Compression gauges are available as screw-in types and hold-in types. The screw-in type is slower to use, but eliminates the possibility of a faulty reading due to escaping pressure. A compression reading will uncover many problems that can cause rough running. Normally, these are not the sort of problems that can be cured by a tune-up. Vacuum gauges are also handy for discovering air leaks, late ignition or valve timing, and a number of other problems. Fig. 32 Proper information is vital, so always have a Chilton Total Car Care manual handy
Fig. 33 Two styles of oil drain pan. The screw-in type on top is more accurate and is easier to use, but is more expensive.
Fig. 34 A variety of tools used for spark plug installation and timing adjustment.
TIMING LIGHTS
There are two basic kinds of timing lights- DC powered timing lights, which operate from your vehicle's battery, and AC powered timing lights, which operate on 110 volt house current. Of the two, the DC light is preferable because it produces more light to see the timing marks in bright daylight.
Regardless of what kind is used, the light normally connects in series with the No. 1 spark plug using an adapter. Models that are more expensive sometimes use an inductive pickup, which simply clamps around the plug wire and senses firing impulses. Inexpensive models use alligator clips; one clamps onto the connection between the plug and the plug wire, and the others clamp onto the vehicle battery terminals.
Some timing lights will not work on electronic ignition systems, so unless you still own a vehicle equipped with points, check to make sure the timing light you buy will work.
The biggest problem you will probably have when using a timing light is trying to see the timing marks on the crankshaft pulley. Before you time the engine, mark the appropriate timing indicators with fluorescent paint or chalk. Stay out of direct sunlight when you time the engine and buy a timing light with a xenon light, not a neon light. Timing lights that use a xenon tube provide a much brighter flash than those that use a neon tube do. Fig. 35 A modern electronic timing light. Note the inductive pick-up clamp.
TACHOMETER
You're not going to have much use for the dwell function of a dwell tachometer on late-model vehicles as it is controlled by the computer and is not adjustable. However, if you need to set the base idle speed, and it is adjustable, the tachometer will provide more accuracy than one on your instrument cluster. You don't need one of those gigantic analyzers to set the rpm on your vehicle. Prices range from less than $50$100 and more. Make sure you get a dwell-tach or tach that is compatible with your vehicle's ignition system.
Dwell-tachs are simple to hook up. Some dwell-tachs are powered by the circuit being tested, some operate off the vehicle battery, and some have their own power source. Electronic ignition systems have specific connection procedures and you'll have to check with your dealer to determine the tach hook-up.
There are several Multi-Meter/Engine Analyzers on the market which provide the functions of a Multi Meter and a Engine Analyzers (Dwell & Tach). Fig. 36 Typical aftermarket dwell tachometer- used to check dwell on old point type ignition, and RPM on point and electronic ignition systems.
Electrical and Diagnostic Tools
JUMPER WIRES
Never use jumper wires made from a thinner gauge wire than the circuit being tested. If the jumper wire is of too small a gauge, it may overheat and possibly melt. Never use jumpers to bypass high resistance loads in a circuit. Bypassing resistances, in effect, creates a short circuit. This may, in turn, cause damage and fire. Jumper wires should only be used to bypass lengths of wire.
Jumper wires are simple, yet extremely valuable, pieces of test equipment. They are basically test wires which are used to bypass sections of a circuit. Although jumper wires can be purchased, they are usually fabricated from lengths of standard automotive wire and whatever type of connector (alligator clip, spade connector or pin connector) that is required for the particular application being tested. In cramped, hard-to-reach areas, it is advisable to have insulated boots over the jumper wire terminals in order to prevent accidental grounding. It is also advisable to include a standard automotive fuse in any jumper wire. This is commonly referred to as a "fused jumper". By inserting an in-line fuse holder between a set of test leads, a fused jumper wire can be used for bypassing open circuits. Use a 5 amp fuse to provide protection against voltage spikes.
Jumper wires are used primarily to locate open electrical circuits, on either the ground (-) side of the circuit or on the power (+) side. If an electrical component fails to operate, connect the jumper wire between the component and a good ground. If the component operates only with the jumper installed, the ground circuit is open. If the ground circuit is good, but the component does not operate, the circuit between the power feed and component may be open. By moving the jumper wire successively back from the component toward the power source, you can isolate the area of the circuit where the open is located. When the component stops functioning, or the power is cut off, the open is in the segment of wire between the jumper and the point previously tested.
You can sometimes connect the jumper wire directly from the battery to the "hot" terminal of the component, but first make sure the component uses 12 volts in operation. Some electrical components, such as fuel injectors, are designed to operate on about 4 volts, and running 12 volts directly to these components will cause damage.
TEST LIGHTS
The test light is used to check circuits and components while electrical current is flowing through them. It is used for voltage and ground tests. To use a 12 volt test light, connect the ground clip to a good ground and probe wherever necessary with the pick. The test light will illuminate when voltage is detected. This does not necessarily mean that 12 volts (or any particular amount of voltage) is present; it only means that some voltage is present. It is advisable before using the test light to touch its ground clip and probe across the battery posts or terminals to make sure the light is operating properly.
Do not use a test light to probe ignition spark plug or coil wires. Never use a pick-type test light to probe wiring on computer controlled systems unless specifically instructed to do so. Any wire insulation that is pierced by the test light probe is a good candidate for failure. Most vehicle manufactures recommend against this, some also recommend against back-probing. Back-probing is where the tip of the probe is forced into the back of the connector. Refer to the specific vehicle manufacturers for recommendations.
Like the jumper wire, the 12 volt test light is used to isolate opens in circuits. But, whereas the jumper wire is used to bypass the open to operate the load, the 12 volt test light is used to locate the presence of voltage in a circuit. If the test light illuminates, there is power up to that point in the circuit; if the test light does not illuminate, there is an open circuit (no power). Move the test light in successive steps back toward the power source until the light in the handle illuminates. The open is then between the probe and a point which was previously probed.
The self-powered test light is similar in design to the 12 volt test light, but contains a battery in the handle. It is most often used in place of a multimeter to check for open or short circuits when power is isolated from the circuit (continuity test).
The battery in a self-powered test light does not provide much current. A weak battery may not provide enough power to illuminate the test light even when a complete circuit is made (especially if there is high resistance in the circuit). Always make sure that the test battery is strong. To check the battery, briefly touch the ground clip to the probe; if the light glows brightly, the battery is strong enough for testing.
A self-powered test light should not be used on any computer controlled system or component. Even the small amount of electricity transmitted by the test light is enough to damage many electronic automotive components. Fig. 37 Test lights are simple to use, however check manufacturers recommendations before probing any wires or connectors.
MULTIMETERS
Multimeters are an extremely useful tool for troubleshooting electrical problems. They can be purchased in either analog or digital form and have a price range to suit any budget. A multimeter is a voltmeter, ammeter and ohmmeter (along with other features) combined into one instrument. It is often used when testing solid state circuits because of its high input impedance (usually 10 megaohms or more). A brief description of the multimeter main test functions follows: Voltmeter- the voltmeter is used to measure voltage at any point in a circuit, or to measure the voltage drop across any part of a circuit. Voltmeters usually have various scales and a selector switch to allow the reading of different voltage ranges. The voltmeter has a positive and a negative lead. To avoid damage to the meter, always connect the negative lead to the negative (-) side of the circuit (to ground or nearest the ground side of the circuit) and connect the positive lead to the positive (+) side of the circuit (to the power source or the nearest power source). Note that the negative voltmeter lead will always be black and that the positive voltmeter will always be some color other than black (usually red). Ohmmeter- the ohmmeter is designed to read resistance (measured in ohms) in a circuit or component. All ohmmeters will have a selector switch which permits the measurement of different ranges of resistance (usually the selector switch allows the multiplication of the meter reading by 10, 100, 1,000 and 10,000). Since the meters are powered by an internal battery, the ohmmeter can be used as a self-powered test light. When the ohmmeter is connected, current from the ohmmeter flows through the circuit or component being tested. Since the ohmmeter's internal resistance and voltage are known values, the amount of current flow through the meter depends on the resistance of the circuit or component being tested.
The ohmmeter can also be used to perform a continuity test for suspected open circuits. In using the meter for making continuity checks, do not be concerned with the actual resistance readings. Zero resistance, or any ohm reading, indicates continuity in the circuit. Infinite resistance indicates an opening in the circuit. A high resistance reading where there should be none indicates a problem in the circuit. Checks for short circuits are made in the same manner as checks for open circuits, except that the circuit must be isolated from both power and normal ground. Infinite resistance indicates no continuity to ground, while zero resistance indicates a dead short to ground.
Never use an ohmmeter to check the resistance of a component or wire while there is voltage applied to the circuit. The voltage could severely damage the meter.
Ammeter- an ammeter measures the amount of current flowing through a circuit in units called amperes or amps. At normal operating voltage, most circuits have a characteristic amount of amperes, called "current draw" which can be measured using an ammeter. By referring to a specified current draw rating, then measuring the amperes and comparing the two values, one can determine what is happening within the circuit to aid in diagnosis. An open circuit, for example, will not allow any current to flow, so the ammeter reading will be zero. A damaged component or circuit will have an increased current draw, so the reading will be high.
The ammeter is always connected in series with the circuit being tested. All of the current that normally flows through the circuit must also flow through the ammeter; if there is any other path for the current to follow, the ammeter reading will not be accurate. The ammeter itself has very little resistance to current flow and, therefore, will not affect the circuit, but it will measure current draw only when the circuit is closed and electricity is flowing. Excessive current draw can blow fuses and drain the battery, while a reduced current draw can cause motors to run slowly, lights to dim and other components to not operate properly. Fig. 38 Combination Multi-Meter and Engine Analyzer makes these the most important diagnostic tools you own. Pro model on right has inductive pick-up
SCAN TOOLS
All late-model vehicles utilize computer modules to monitor and control the functions of on-board systems. These modules are known by many names such as Engine Control Unit (ECU), Engine Control Module (ECM), Powertrain Control Module (PCM) and Vehicle Control Module (VCM) just to name a few. When problems occur in control circuits, these modules record a diagnostic trouble code which can be used to help solve the problem. Over the years, there have been many different types of systems, each with their own unique way of retrieving these codes. On a good number of the older systems, the stored codes were flashed on various trouble lights (found in the dashboard) once a small jumper wire was placed across the proper diagnostic terminals. However the use of a hand-held scan tool was still preferred for these systems.
For some models produced during the 1995 model year and on almost every single 1996 and later model, a new form of trouble codes was developed which required the use of a scan tool. On Board Diagnostic-II (OBD-II) compliant vehicles use a 5 digit, alpha-numeric code which would be difficult or impossible to read using a flashing light, therefore trouble code reading on an OBD-II compliant requires a scan tool.
There are many manufacturers of these tools, but a purchaser must be certain that the tool is proper for the intended use. If you own a scan type tool, it probably came with comprehensive instructions on proper use. Be sure to follow the instructions that came with your unit
The scan tool allows any stored codes to be read from the computer module memory. The tool also allows the operator to view the data being sent to the computer control module while the engine is running. This ability has obvious diagnostic advantages; the use of the scan tool is frequently required for component testing. The scan tool makes collecting information easier; the data must be correctly interpreted by an operator familiar with the system.
An example of the usefulness of the scan tool may be seen in the case of a temperature sensor which has changed its electrical characteristics. The computer module is reacting to an apparently warmer engine (causing a driveability problem), but the sensor's voltage has not changed enough to set a fault code. Connecting the scan tool, the voltage signal being sent to the module may be viewed; comparison to normal values or a known good vehicle reveals the problem quickly. Fig. 39 Typical aftermarket scan tool used to access diagnostic codes from the Electronic Control Module.
Fig. 40 This Auto Xray® scan tool uses manufacturer specific cables to interface with the various connectors.
SOLDERING GUN
Soldering is a quick, efficient method of joining metals permanently. Everyone who has the occasion to make electrical repairs should know how to solder. Electrical connections that are soldered are far less likely to come apart and will conduct electricity far better than connections that are only "pig-tailed" together.
The most popular (and preferred) method of soldering is with an electric soldering gun. Soldering irons are available in many sizes and wattage ratings. Irons with high wattage ratings deliver higher temperatures and recover lost heat faster. A small soldering iron rated for no more than 40 watts is recommended for home use, especially on electrical projects where excess heat can damage the components being soldered.
There are three ingredients necessary for successful soldering- proper flux, good solder and sufficient heat.
Flux
A soldering flux is necessary to clean the metal of tarnish, prepare it for soldering and to enable the solder to spread into tiny crevices. When soldering electrical work, always use a resin flux or resin core solder, which is non-corrosive and will not attract moisture once the job is finished. Other types of flux (acid-core) will leave a residue that will attract moisture, causing the wires to corrode.
Good Solder
Tin is a unique metal with a low melting point. In a molten state, it dissolves and alloys easily with many metals. Solder is made by mixing tin (which is very expensive) with lead (which is very inexpensive). The most common proportions are 40/60, 50/50 and 60/40, the percentage of tin always being listed first. Low-priced solders often contain less tin, making them very difficult for a beginner to use because more heat is required to melt the solder. A common solder is 40/60 which is well suited for all-around general use, but 60/40 melts easier, has more tin for a better joint and is preferred for electrical work.
Sufficient Heat
Successful soldering requires that the metals to be joined be heated to a temperature that will melt the solder, usually somewhere around 360–460°F (182–237°C), depending on the tin content of the solder. Contrary to popular belief, the purpose of the soldering iron is not to melt the solder itself, but to heat the parts being soldered to a temperature high enough to melt solder when it is touched to the work. Melting flux-cored solder on the soldering iron will usually destroy the effectiveness of the flux. Fig. 41 These are several types of soldering tools and guns
How to Solder
- Soldering tips are made of copper for good heat conductance, but must be "tinned" regularly for quick transference of heat to the project and to prevent the solder from sticking to the iron. To "tin" the iron, simply heat it and touch flux-cored solder to the tip; the solder will flow over the tip. Wipe the excess off with a rag.
- After some use, the tip may become pitted. If so, dress the tip smooth with a fine file and "tin" the tip again.
- An old saying holds that "metals well-cleaned are half soldered". Flux-cored solder will remove oxides, but rust, bits of insulation and oil or grease must be removed with a wire brush or emery cloth.
- For maximum strength in soldered parts, the joint must start off clean and tight. Weak joints will result in gaps too wide for the solder to bridge.
- If a separate soldering flux is used, it should be brushed or swabbed on only those areas that are to be soldered. Most solder contains a core of flux and separate fluxing is unnecessary.
- Hold the work to be soldered firmly. It is best to solder on a wooden board, because a metal vise will only rob the piece to be soldered of heat and make it difficult to melt solder. Hold the soldering tip with the broadest face against the work to be soldered. Apply solder under the tip close to the work. Apply enough solder to give a heavy film between the iron and piece being soldered, moving slowly and making sure the solder melts properly. Keep the work level or the solder will run to the lowest part, and favor the thicker parts, because these require more heat to melt the solder. If the soldering tip overheats, (the solder coating on the face of the tip burns up). The tip should be re-tinned.
- Once the soldering is completed, let the soldered joint stand until cool.
Fig. 42 If necessary, dress a pitted tip with a fine file
Fig. 43 Tinning the soldering iron
Fig. 44 Wipe the excess solder from the iron while hot
Fig. 45 The correct method of soldering. Let the heat transferred to the work melt the solder
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