A Serious Hobbyist's look at Tools for the Automotive Workshop
Part 2 - Diagnostic and specialty tools
<< On to ... Part 1 - Hand Tools and Safety Equipment >>
© By: John T. Blair (WA4OHZ)
1133 Chatmoss Dr., Va. Beach, Va. 23464; (757) 495-8229
Originally written: circa 1989
Last update: Jan 31, 2006 - added pictures of the various tools and changed some of the wording.
Now lets move on to some more specialized tools that will come in very handy for troubleshooting and diagnosing problems. These are usually be purchased as needed.
First in my book is an analogue multimeter. The digital ones are OK but I prefer the old fashioned ones with the real meter movement. Probably the best source for one of these is Radio Shack. A good meter can be purchased for about $30 on sale. This will allow you to measure voltage (AC or DC), current, and resistance. This tool is a must for trouble shooting any electrical problem. I know most mechanics just use the Test light (little screwdriver looking thing with a light bulb in it, but that just doesn't cut it for me although it is better than nothing). It is pretty much a go, no go, tool.
A vacuum gauge is used to measure the vacuum in the car's engine and they are great diagnostic tools. Many old timers use them for setting carbs and timing. Like a compression gauge, the vacuum gauge lets you get a feel for what is happening in the engine, like sticking valves, ignition and valve timing, or if any of the valves are burned, and more. They can also be used for checking fuel pressure on low pressure (non-fuel injected systems).
Another vacuum related tool is the MityVAC or Vacuum Pump Kit. In addition to having a vacuum gauge, it has a trigger grip to allow you to create a vacuum for testing all kinds of diaphragms, etc. as well as read vacuum and you can see how long a part holds a vacuum. They cost from about $25 to about $70 depending on what accessories you get with in. Many come with a great book on how to use on in troubleshooting engine problems. The newer the car is the more vacuum operated controls there are, like the heating system.
A compression gauge is used to check how much pressure can be created in a cylinder. A compression test, along with a vacuum gauge, is about the only way of telling if an engine has a blown head gasket, bad valves, or rings without removing the head. If you buy one, spend the extra money and get the one that have a long flex hose and actually screw into the spark plug holes instead of the inexpensive ones you have to push on and hold. In many of the newer cars you can't get these inexpensive ones to the spark plug holes.
For tuning up older cars with points, (pre 1980 - Before Computers), you will need a timing light and a dwell/tach meter. I prefer the DC powered timing light (about $50). This type of timing light clips onto the cars battery to power the light, and clips onto #1 spark to pickup when #1 spark plug fires. This triggers its high intensity light which can be seen even on a sunny day. The dwell meter is used to set the points and the tachometer is used to set the engines idle speed.
and ODB
system. There are more complex scanners available (like the made by autotap.com) that connect to a lap top computer and let
you monitor a many of the parameters real time, retrieve error codes, and
reset codes. These typically run from $300 to over $500.
Moving on to some more specialized tools, inevitably you will need a
couple of gear pullers (2 and or 3 jaw) for removing pulleys and
gears from things. I'd suggest that maybe you get a 3 jaw puller set.
Otherwise wait until you need the puller and buy it against the job. There
are 
special
pullers for AC compressor clutches, Pitman arm, power steering pump
pulleys, hub, axles and bearings you will need a special set of pullers. A
hub puller is quite large and it bolts to the hub. The axle puller is
smaller and has a slide handle. The puller can be reversed for pulling
bearings and races. (Harbor Freight has a set for about $33.) 
Now that's what I call a pretty nice tool box. Unfortunately, we have an expensive hobby and now we start filling our garage, not just the tool box, with tools. These tools will also be a little more expensive.
Now we'll go back to some tools that don't find in the tool box. An
air compressor and the associated air tools, while not necessary,
are a great time 
saver
and make working on car a lot easier. One of the most important jobs in
restoring a car, is fighting rust. When I restore a car, every metal part
is removed, cleaned and painted. So here again an air compressor will pay
for itself. I would not recommend anything smaller than a 4hp compressor
with a 20 gallon accumulator. I grew 
up
with one like this, my dad has had his Craftsman compressor for over 20
years. But it has trouble keeping up with the sanders, sand blasters, etc.
So when I went to purchase mine, I went up one size, to a Craftsman 5 hp
with a 30 gallon tank (it cost about $500). The rule of thumb is the
"bigger the better", but your pocket book and 
available space will control your spending. Compressors of less
than 4hp use 115V while the 4hp and larger use 220V. If you opt for a
larger one, you might have to run a new power line from your service
panel.
The horse power (hp) rating of the electric motor (i.e.. 5 hp., 10 hp.,
etc.). Lately, the marketing departments of the various compressor
manufactures have been playing games with the hp ratings. It seems that
they are rating them based on the maximum current the motor will draw
(when starting) and not the running current. So beware. 1 hp is about 750
Watts. So a 5 hp motor should consume about 5x750=3750 Watts or 3.7
Kilowatts (KW). To calculate the current required by the motor divide the
Watts by the Voltage (either 115 or 220). So a 5 hp motor will draw at
least 3750/115 = 32.6 amps on a 115V circuit, or 3750/220 = 17 amps on a
220V circuit. This assumes that the motor is 100% efficient, which it
isn't. House hold wiring usually has 2 types of circuits - the 110V (also
referred to as 115V or 120V) used for most electrical lighting and small
appliances. The maximum a 115V circuit will be rated for is about 
30 amps.
Heavy appliances like an electric dryer, water heater, and stove all
usually run in a 220V circuit. So you see that a 5 hp compressor will
require a 220V circuit in your shop.
To help dry the air (remove moisture), you will need a dryer attached to the output of the compressor. My compressor sits by the front of the garage and I have 50' of air hose connected directly to the dryer. Originally the dryer was connected directly to the compressor and consequently could not pull any moisture out of the air. To condense the moisture out, there must be some distance between the output of the compressor and the dryer, 2 inches just didn't hack it. I got some copper tubing and wrapped it around a 2 liter Coke bottle. I connected 3 foot length of air hose to each end of the coil with one end going to the output of the compressor and the other end going to the dryer. This alone pulls a lot of water out of the air. In addition, I can submerge the coil in a bucket of water to help cool the air even more.
Next, you will need some paint guns. Since the primer is relatively
thick, a pressure feed gun is usually used. This type gun lets the
compressed air into the paint tank 
to
pressurize it, thereby forcing the paint out. You can skimp on the cost of
this gun as the primer will get sanded and smoothed. My gun for priming is
an inexpensive Sears pressure/siphon gun (found at a yard sale for $5).
For painting the top (color) coats a siphon feed gun is used. These
guns let the air blow past the pickup tube, creating a vacuum and sucking
or siphoning up the paint. These guns are more expensive; mine is a SEARS
and cost about $70. A professional gun like a Binks can start at about
$150. Relatively recently a new type of gun has hit the market, a High
Volume Low Pressure (HVLP). These guns are supposed to reduce over spray,
and put more paint on the surface. I got a Harbor Freight one a couple of
years ago for Christmas. I've used it quite a bit, and I like it better
than any of the other spray guns I have.
There is also the Powder coating systems. However, for these you need an oven to cook the parts in after they have been sprayed.
Now that you have a compressor, you have an excuse to get some of those
nice air tools you've been looking at, like a 1/2" drive impact
wrench (from $40 up). This really makes changing tires easy and
reduces the busted knuckles when trying to undo a really rusted bolt.
(Note, I purchased a 2nd 1/2" impact wrench. It's a Champbell Hausfeld
Professional PL1502 for about $65 from Northern Hydraulics. It has 
about
twice the umph of my $30 wrench. I love it, it has replaced my cheap
impact wrench as my work horse.). Another great air tool is a 3/8 drive
ratchet (about $30), and I don't know how I ever lived without it. No
more hand cranking on the ratchet, just press the trigger and it does all
the work! One word of caution though, Don't use it to break nuts
and bolts loose. If you do, you will drastically reduce its life span. I
broke the gears on my first one, trying to break a bolt loose. Use either
an impact wrench or a manual ratchet to break bolts loose. Also, DO
NOT use an impact wrench or air ratchet 
to
fully tighten nuts and bolts. They give no feed back or feel and it
is easy to break bolts off with them. If using to run the nut or bolt
down, always set the tool to its lowest power setting and stop when the
impact wrench start to make the familiar banging sound, or the air ratchet
starts to pull in you hand. Then switch to a regular ratchet or torque
wrench to finish the job.
A 1/4" die grinder ($25) is a high speed tool and comes in straight and angled. I bought an angled grinder and an arbor and a cutting wheel. This makes short work for cutting off bolts and such. It can also be used to cut sheet metal - like a section from a fender. There is also a rubber disked arbor that you can attach a 3" sanding pad for it and some stick on 80 grit sandpaper. There are also various cutting burrs and grinding stones.
For
doing body work a dual action "DA" sander (about $40) and an
inline sanders (about $40) are real time savers. 
Speaking of body work, Harbor Freight has a nice set of body hammers and dollies for under $20.
For cleaning paint and rust off of metal parts I use a 4" high
speed (10,000 rpm) grinder (from $40 to $100). The grinding stone
can be removed and replaced with a knotted wire brush. Unfortunately,
these brushes are pretty expensive (about $15 each) they are 
the only ones rated to handle the 10,000 + rpm's of the grinder. For
relatively large areas, this high speed wire wheel does a better job than
paint stripper. I purchased an inexpensive one for $40 from Harbor
Freight. My dad borrowed and loved it, so he bought a Makita for $55.
However, we both like the one from Harbor Freight better. The 2 drawbacks
to the Makita are, 1 - the arbor size is metric M10x1.25. Most discount
houses sell the standard 5/8" x 11 brushes but very few handle the
M10x1.25. Consequently, getting the wire wheels is harder and more
expensive. The second problem is the Makita's safety guard is screwed to
the case and cannot be rotated. Many times we wanted to move the guard
around
to allow better access when cleaning a part. When using these grinders,
you should wear some sort of eye protection. I've purchased a face shield
for about $12 from Northern Hydraulics. Since I wear glasses, goggles tend
to fog up. You should also use some kind of hearing protector. I bought a
pair of "Mickey mouse" ears from Northern Hydraulics for about $8.
Finally, you should wear a pair of leather gloves. I've had the wire wheel
get away from me and nick my hands. It took forever to heal, and left some
nice scars.
In addition to the high speed grinder, the 3/8" (VSR) electric drill can be use to clean parts by chucking up a wire wheel. The wire wheels are about $5 and an arbor to hold the wheel is about $2.
For small parts or places that the grinder can not get to, a
sandblaster is great! I started with a siphon blaster with a 50
pound
sand tank (from $50 to $100). I moved up to a Harbor Blast Cabinet and to
a pressure blaster. For more information check out my article on media
blasting.
If you plan on doing any major work like pulling an engine or pulling a body off a chassis, an engine crane is a must. I purchased mine, a 2 ton hoist, for about $200. While these can be rented, I figured I had to pull and replace the engine and the body of my Morgan, and pull and replace the engine and body of my '75 Bricklin. At about $35 per day rent, I could just about purchase one for the rental fee, so I did and been saving money ever since. To cut down on the space it requires, when not in use, I disassemble mine and tie all the parts against the wall of my garage.
A hydraulic press is a useful item although expensive. While you can send the work out to be done, unless you know someone, it can get expensive. Depending on the type of work you are doing, this will be one of the least used tools in your shop. You use them to press on or off Universal Joints, bushings, and bearings. I had to pay $30 to have the old bearings pressed off and a new bearing pressed into the steering knuckle of my Voyager van. Since I've got 2 Voyagers and had to do the job to both, that's 4 times. Almost the cost of a press. However, it's nice to be able to press bearings on and off when you need to. Harbor Freight as several nice presses for about $120 - $220.
Another item is a welder. There are 3 basic types of welders: oxy-acetylene, arc, and MIG or wire feed. While the MIG (or wire feed) welder is the most expensive of the 3. MIG stands for welding for dummies! Not really it stands for Metal Inert Gas. I would suggest a MIG welder for an initial investment. But is the easiest to learn to use. Most welding on a car is replacing thin sheet metal panels. This is what the MIG does best. The MIG welder doesn't generate the heat the other 2 welders do. The wire feed feature makes welding easier for the hobbyist use. I'm purchased a Lincoln SP100 MIG welder for about $600. To add the gas regulator, bottle, hood and gloves cost about $200 more. The MIG and the wire-feed welders are the same unit. The difference is for MIG you add the gas regulator and bottle of gas. There is a different sleeve that goes inside the cable that feeds the wire also to handle the different size diameter of the welding wire. The MIG wire is about .023" while the gas less wire is has flux in it core and is about .035". If you decide to purchase a MIG welder, look for one that has continuously variable wire feed speed and voltage settings vise the 4 to 6 click stop settings. This way, you can adjust the machine to fit you and you don't have to learn vary your welding to meet the machine.
I must admit that my dad already has the oxy-acetylene (with the 5 foot tall tanks) and an arc welder so I have access to them and haven't had to buy either of these. Taking a quick look at oxy-acetylene welders. What are they good for? A very good welder can weld about anything with one of these units, but it takes a long time to become that good. Due to the heat generated, it is very ease to warp a thin sheet metal panel on a car. The other two things that are nice about oxy-acetylene welders, is the heat and cutting. If you need to bend or shape a piece of metal, you can get it cherry hot and then bend or shape it a lot easier than doing it cold. Another nice thing about the heat, is if you have a nut or bolt that doesn't want to move, in many cases you can use the "hot wrench" technique. Get the nut or the metal surrounding the bolt hot. This heat will help loosen the nut or bolt. Finally, there is the cutting torch aspect. While the cuts aren't the smoothest it does cut metal nicely and quickly. I find that many times I need to cut up something, like a car that my friends and I are stripping. To move my dad's 5 foot tanks from his place to mine is a real chore, and to move some of the things I'm working on to his place is even harder. Consequently, I'd prefer a slightly smaller set of bottles. Something in the neighborhood of 40 to 60 cubic feet. This setup has the advantage of portability. The only drawback is that the bottles of gas don't last as long. It's a real pain to run out of gas on a Friday night and not be able to use the equipment until Monday night after the welding suppliers open Monday. One final note on oxy-acetylene, if you get a setup, be sure to get flame arrestors. These connect to the hoses, and are designed to keep the flame from walking back into the lines and causing the tanks to explode. Welding can be very useful, but like a lot of tools (especially electric saws) it can be very dangerous. Look around where you are going to weld. You don't want anything that is flammable near by. If you are a home hobbyist, try to do all you welding and cutting outside. You don't want the sparks to catch something on fire in your garage. Also be careful when welding on a car. Again, look at what you plan on welding, both sided. Don't try to weld on the bottom of the floor pans, and still have the seats, carpet, or insulation material in place. They will catch on fire. If you decide to purchase any type of welder, check with your local Vocational Technical Schools, or Community Colleges. Many offer welding courses. These are definately worth the cost. You will got through a lot of gas, electricity, and metal learning to weld. All this is covered in the cost of the class. Plus you have an instructor to help you with the technique.
In closing, the tools just mentioned represent quite a sizable investment and will start to set up a very nice work shop. You may not need or want all the tools I've described here. But you now have an idea of some of the tools that are available and what they are used for. You don't have to go out and purchase all the tools at once. Keep a list of desired tools prominently displayed or just hand it the your wife, girl friend and kids (or all three). There is always a tool for every gift giving occasion.
If you aren't already familiar with the companies I've mentioned, here are the names of several mail order tool houses. If you don't have their catalogues, simply give them a call and they'll send you one. They make great reading. You can spend hours just drooling over all the tools you don't have and dream of how much easier life would be if you only had that tool.
Enjoy your Car
John
Harbor Freight Tools
3491 Mission Oaks Blvd
P.O. Box 6010
Camarillo, Ca. 93011-6010
(800) 423-2567 - They have a wide range of items from shop rags to milling machines.
Kitts Industrial Tools
22384 Grand River Ave.
Detroit, Mi. 48219
(800) 521-6579 - They have a wide range of items.
Sears Tool catalogue, Can be picked up at most Sears stores.
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