Why even have a safety page?
The automobile was invented to replace the horse. This was because horses need food, shoes, medical and janitorial care, housing, etc. even when you aren't riding them or using them to pull a wagon. If you ignore your car for two weeks, it might be a little cranky, but it won't be DEAD.
I have never owned a horse myself, but have had dealings with quite a few of them over the years. My eldest little-sister (Hi Jan!) has owned many, (sometimes as many as 5 at once). She hasn't needed anybody's help with a horse for quite a few years, but when she was younger I got to help out on a regular basis.
During the course of my relationship with those ponies and horses, I have been bitten, stepped on, sat on, rolled on, kicked, butted, bucked off, scrubbed off, rubbed off, laughed at, and just in general, abused by the creatures. It's not hard to understand why the automobile was invented to replace them.
But this site isn't about horses, it's about cars. Specifically, about working on cars. Over the course of my relationships with the various cars I have known and tended to, I have been bitten, burned, cut, rolled on, crushed, lacerated, abraded, set afire, temporarily blinded, deafened, dislocated, sprained, strained, torn, and in general, hurt by them. I would be a fool if I didn't warn you that:
WHILE WORKING ON YOUR CAR!
are killed or injured every day while working on cars. Please be careful.
If you choose to work on your own (or anybody else's) car please follow
all of the safety rules below. If something seems unsafe, it probably
is, don't do it. If you do it anyway and hurt yourself, please
don't write to tell me about it. If you survive, come by and see me
and we'll compare scars.
General: It is a good idea to wear safety goggles or safety glasses all the time when you work on your car. Long sleeves will give you a measure of protection from some stuff, but can get tangled in belts and stuff so are a tradeoff, keep the sleeves buttoned. Neckties are a no-no, (in general and especially when working on a car) ditto sandals. Long hair? put it under a hat, or wear a hair net to keep it out of the moving parts. A guy in Kansas had his scalp ripped off by a rotating driveshaft while he was working under his car. Open flames? Two guys in New York were burned to death while trying to thaw a frozen fuel line with a propane torch. I wish I had all the money I've spent to have fire extinguishers recharged. Keep an ABC fire extinguisher handy, just in case.
Batteries: Disconnect the battery. Period. I know, I know,
you'll have to reset the pushbuttons on the radio, but that's better
than welding a wrench to your starter and possibly burning your car(not
to mention the garage it is in) to the ground. I have seen and experienced
some very bad burns that occurred when someone shorted out the main
battery voltage with a wrench and then couldn't let go of the wrench
fast enough. Even if you aren't working anywhere near the battery,
the wiring stretches from bumper to bumper. All you have to do is
short circuit a hot wire to ground and it can get red-hot in a fraction
of a second. This can start a fire or just give you a nasty burn on
your little pinkie, not to mention cause the car to lurch forward
or backward if you happen to short the starter wires and the car is
in gear. The car is not likely to start accidentally if the battery
is disconnected. Batteries can explode. I didn't believe
this until one blew up while I was connecting jumper cables to it.
It made a very loud noise, and splattered battery
acid all over the place, not to mention flinging jagged bits of plastic
in all directions at very high velocity. I think many injuries could
be prevented if people always disconnected the battery cables before
working on the car. (Tip: you only need to disconnect one of the cables
to effectively disconnect the battery.) It really doesn't matter too
much which one, but it seems to be a bit better for the delicate electronics
if you disconnect the positive (+) one. If you are trying to diagnose
an electrical problem, of course you'll have to leave the battery
connected, be extra careful.
Burns: Some parts of the car get very hot, and stay hot for quite a while after the engine is shut off. I have seen cars with parts of the exhaust system glowing red hot after the car has been run only a short distance. Don't touch the hot parts (duh). Let things cool off before you work on them.
Cuts and scrapes: Some of the parts of the car are as sharp as a razor! Wear gloves if you can, be very careful if you can't. Inside of door panels is a particularly nasty spot for getting cuts.
Gasoline: A cup of gasoline has the same potential explosive force as a stick of dynamite! It also can cause burns to your eyes or skin. Don't screw around with it if you are at all clumsy, stupid, stoned, drunk, or unlucky. If you spill some, clean it up at once. Dispose of rags in a closed metal container. If you are working on a car with a pressurized fuel system, relieve the pressure before you loosen any hoses. Work in a well ventilated place. Breathing gasoline fumes will make you stupid, and dead.
Fan belts: Not very dangerous as long as the engine isn't running, cranking, or likely to start unexpectedly. Since the belts wrap around various pulleys and sprockets, don't get your fingers trapped between the belt and the pulley. When the engine is running, however, these little guys can reach right up and grab a sleeve (with arm attached) and yank it down amongst the whirling and grinding parts faster than you can blink. If this happens to you it will ruin your whole day.
Radiator: That pretty green stuff in your cooling system is poison! It can kill your kids, your pets, and you! It tastes sweet and looks pretty and green, so kids and pets will drink it if you leave it out. It also gets very hot when the engine is running and the system builds up enough pressure to spray scalding hot coolant everywhere when you open the radiator cap. The normal pressure for a cooling system is about 14-17 psi, and the normal operating temperature is near the boiling temperature of water. If the engine has been running, be very careful when you open the cap. Cover it with a rag and open it slowly to the first detent to give it a chance to relieve the pressure before you remove it the rest of the way. It is also a good idea to turn your face away, just in case... Best: don't open the radiator cap until the engine has cooled off completely.
Spark Plug Wires: The ignition system on some cars can develop over 30,000 volts. That is THIRTY THOUSAND volts, it probably won't kill you, (at least it hasn't killed me yet) but it can really screw up your digital watch and probably wouldn't be too good for a pacemaker if you happen to have one. When you accidentally get zapped, it makes you jerk away and usually bash your elbow on something else under the hood, which can be very painful, not to mention embarassing.
The whole car: Don't get under it. Block the wheels. Work on level ground. Make sure that the Park Brake is set securely. If your car has an automatic transmission, make sure it is in PARK. If it has a manual transmission, make sure it's in NEUTRAL and BLOCK THE WHEELS, in front and in back of the tire. Nothing is quite as embarrassing as being run over by your own car, trust me, I know. If you do need to get under it, support it securely with proper jackstands, NEVER get under a car that is supported only by a jack.
Wheels and tires: Tires can explode, don't put too much air in them. Wheels can have sharp edges and rusty spots. Sometimes the steel wires from the belts in the tire will come out of the rubber, stabbing you when you run your hand over it. Back injuries are common because of poor lifting techniques, lift with your legs, not your back. Split-rim type wheels kill more mechanics than any other part of the vehicle. NEVER try to fix a flat tire on one yourself! I've fixed probably a hundred of them over the years, from regular pick-ups to big transport trucks to big old backhoes. Every single one scared the sh*t out of me!
Distractions: Anytime you are working on a car, it is wise to avoid distractions. You need to keep your wits about you. There is danger and pain just inches away. Stay focused on the job at hand, if you find your mind wandering, take a break, let your subconscious work on the problem for a while
If you have managed to read all of this page, thanks. The concept of safety is a lot more than just memorizing a lot of rules, it's understanding the principles of physics as they apply to your car enough to visualize what could happen, the probability that it will happen, the effects on the human body if it did happen, and the wisdom to always make the correct choice.