A DIY car maintenance program can keep your car in top form and can prevent vacation
A DIY Car Maintenance Program
With summer just around the corner, it won't be long before
millions of Americans take to the highways in celebration
of their annual vacations. Unfortunately, many of those
travelers won't reach their destinations without
suffering a mechanical mishap along the way.
A roadside breakdown is no joke, and you'll only be kidding
yourself if you leave your fate to chance. By
spending a Saturday afternoon doing your own DIY car maintenance checking commonly ignored
components on your car, you'll be one up when you take
those jaunts—or that special journey—you've been
looking forward to all year.
These preventive maintenance steps don't have to cost a
cent. Nor will they require a shopful of tools or the
expertise of a seasoned mechanic. In fact, each procedure
outlined below is one you can do yourself, even if all you
know about cars is how to lift the hood or change a tire. A
few essential tools will come in handy: adjustable
channel-locking pliers, flat- and Phillips-blade
screwdrivers, a utility knife and perhaps a seven-piece set
of combination or socket wrenches (3/8 inch through 3/4 inch or 9mm
through 19mm, metric). If you don't own any tools, consider
buying some to keep in the car. You just might need them on
the road someday.
It seems sensible to begin by opening the vehicle's hood .
. . but it makes even more sense to start by opening your
owner's manual to the section on service and scheduled
maintenance. There the manufacturer itemizes service
procedures by mileage intervals and indicates fluid
capacities, oil and coolant requirements and a number of
other things specific to your car. The manual often
includes photos or illustrations that locate and detail
each maintenance chore clearly. (See the car maintenance diagrams in the image gallery.)
Getting Down and Dirty
Once you've familiarized yourself, at least in theory, with
the things that might need attention under the hood, it's
time to make your move. Don't count on keeping your clothes
clean; just wear something that can get stained. Remove any
watches or metal jewelry that can conduct electricity, and
dispense with belts or buckles that might scratch your
car's finish. Tie up your hair (or wear a hat) if it's long
enough to snag.
Safety first? It's a good practice, so let's start there.
Turn on the headlights, and walk around the car to check
each bulb. Test the high beams and brake lights (with the
help of a friend). Try the turn signals and parking/side
marker lights, too. If a lamp is burned out, be sure to
replace it with one of the same type. To change a headlight
on most cars, first remove the trim door around it; then
loosen the lamp mounting screws, pull the bulb plug and put
in the new unit. Don't turn the longer headlight
alignment screws, or you'll need to re-aim the headlights.
The taillights are usually accessed through removable
panels in the trunk in modern cars. On older models, the
lenses unscrew from the outside.
What to Check Under the Hood
B-WIPERS: Replace the blades if they're worn, and fill the
C-BRAKES: Look for leaks or kinks in the brake lines;
scraping or clinking noises should be checked.
D-SHOCKS: Worn shock absorbers cause your car to wallow and
bounce. Look for a service center sale.
E-TIRES: Tread wear can tell a story if you know what to
look for. If the rubber is in good shape, inflate the tires
to the recommended pressure.
F-LIGHTS: It only takes a few moments to check headlights,
G-EXHAUST: Get under the car and look for corrosion or
looseness in the pipe, muffler or clamp components.
Blades, Breakers and Battery
Inspect the wiper blades for splits and deterioration.
Replace them (by pinching the end clips together and
sliding the flat spine through the four sets of hooked
guides) if they're at all questionable. On some cars, you
may need to change the blade and its holder by
pressing the clip or button located at the end of the wiper
arm. Now's also the time to fill up the washer reservoir
with the recommended fluid and test the system.
Determine what type of fuses or breakers your electrical
system uses by referring to the owner's manual or checking
the fuse box beneath the driver's dashboard or on the
inside or outside fire wall panel. Purchase spare fuses to
match the three or four amperage ratings required. Check,
as well, the operation of your fuel gauge. If it's broken
or erratic, have it repaired before you travel.
Warm weather won't guarantee a trouble-free battery. Time,
corrosion and poor maintenance take their toll in any
season. If there are deposits on the terminal posts and at
the top of the battery, wash the areas with a solution of
two tablespoons baking soda to one quart water. Is the
corrosion well entrenched? Loosen the cable clamps, remove
them from the posts with a cable puller or channel pliers,
then clean the posts and the inside of the clamps with a
small wire brush or a terminal tool. Don't hammer the
clamps in place when you reattach them, or you may ruin the
battery. If the cables have deteriorated and the wiring is
exposed, replace them. Check, too, the cable connections at
the engine block (or chassis) and at the starter solenoid.
They should both be tight and free of dirt. Coat the posts
and clamps with gasket sealer or petroleum jelly to inhibit
Remove the filler caps at the top of the battery, and add
enough distilled water to cover the cell plates if they're
exposed. Inspect the battery hold-down clamps; tighten or
replace them if necessary.
While you're at it, take a look at the alternator drive
belt. The outer face may appear fine, but twist it slightly
to check the tapered sides. A healthy belt shouldn't be
cracked, shiny-smooth or flecked with oil stains. If you
must replace or tighten the belt, don't put excessive
pressure on the alternator housing, or you may distort it;
draw it firmly against the belt so there's about 1/2 inch up-and-down deflection on the longest stretch.
Filters and Breathers
The air filter is one of the least expensive parts on your
car, yet one of the most ignored. On a conventional
carbureted engine, it's located in the round housing above
the rest of the motor; fuel-injected models may house it in
a chamber off to one side. Replace the element if it's been
on the car for more than 24,000 miles (sooner, if you drive
under dusty conditions frequently). A good test is to shine
a light through the ribbed section from behind. It'll be
visible if the filter is OK. Check the gasket between the
filter housing and the carburetor, and the condition of the
corrugated hot air duct, as well.
DRIVE TRAIN: Worn universal or constant-velocity joints can
pose a hazard. Check for excessive play in the drive shaft.
More than a fraction of an inch is too much.
In-line fuel filters should also receive attention if
they're old. The kind threaded to the carburetor should be
removed with two wrenches, one to hold the carb nut and one
to unscrew the filter. You can pull canister types from the
line after you've loosened the hose clamps. Be sure to look
for a direction-of-flow arrow when you install the new
filter. (Fuel-injected engines have pressurized fuel
systems, so it's best to leave their filters to a
The positive crankcase ventilation (PCV) valve-located
within a rubber grommet on the air cleaner housing, valve
cover, intake manifold or oil filler cap-should rattle
freely when shaken. If it doesn't, replace it and the small
breather filter inside the housing or cap. Both parts
simply press into place. In the process, you can inspect
the neoprene ventilation hoses for kinks or tears.
Lubricants and Fluids
The biggest favor you can do your vehicle before a long
trip is to change its oil and filter. Use a box or socket
wrench to remove the crankcase plug in the oil pan, and let
the old oil drain into a leak-free container. Unscrew the
filter (you may need a strap wrench), and let it drain
there as well. Coat the new filter's rubber seal with clean
oil, then tighten the canister in place on the block using
hand pressure only. Replace the oil pan plug
(don't overtighten it), and fill the crankcase to the
capacity specified in the owner's manual.
Change the oil and filter; your car will almost smile.
Automatic transmissions use a high-detergent lubricant
specified by the manufacturer. Usually, the level is
checked when the car is idling and has reached initial
operating temperature. After setting the parking brake,
move the shift lever slowly through all the gear positions,
then back into park. Allow one more minute of idling, then
read the dipstick's "cold" side, if that's indicated. Add
fluid, if necessary, through the dipstick tube until it
reads correctly on the stick. Don't overfill or underfill:
Doing so will affect the transmission's performance.
The power steering system uses automatic transmission fluid
as well. Merely fill the reservoir if the cap stick shows
the level at "add." Keep the fluid level below the cold
mark if you check it cold; any extra fluid will just spew
out when the engine heats up.
Brake fluid must meet the Department of Transportation
standards indicated in the owner's manual. Check the
reservoir at the master cylinder located on the engine
compartment fire wall, and fill it to within 1/2" of the
top if needed. Be careful not to spill any fluid on
finished surfaces, because it removes paint instantly.
Unless you have the tools and experience to check the
differential and manual transmission fluid levels, it's
easier to let a mechanic do those jobs. But don't just
ignore these components, because they can leak and
are very costly to replace.
Overheated engines stop more summertime progress than
anything except flat tires; check your cooling system. For
starters, squeeze the radiator hoses. If they're unusually
stiff, they've probably been overheated. Soft and gooey?
Oil contamination. Or perhaps they've been physically
damaged by tight clamps or contact with a sharp corner.
Replace them—along with heater hoses, choke warming
lines and bypass elbows that show similar characteristics.
Be certain to clean all fittings thoroughly before
installing the new hoses, and always use new worm-drive
clamps rather than trying to reuse the old ones.
Now inspect the fan and water pump belt, using the same
criteria as those used for the alternator drive. Should you
need to replace the belt, test the water pump bearings by
grasping the fan blades or pump shaft and shaking the
assembly up and down while the belt is off. If you can
detect lateral movement of the shaft, the water pump may
need to be replaced, too. (Some cars have electrically
driven radiator fans, so disconnect their terminals while
testing, and concentrate on the pump shaft alone.)
Antifreeze no longer has that single wintertime function.
It's now generally called coolant, and its concentration
can be critical to pump lubrication and warm-weather
driving. If it's been two or more years since you changed
the coolant or the thermostat, consider taking your car to
a service station for a back-flush, thermostat change and
refill. Flushing kits are available to fit your garden hose
if you want to tackle the job yourself. Otherwise, do
without the cleaning, and at least top of the radiator (or
partially fill the small recovery reservoir on newer cars)
with a 50:50 mixture of coolant and water.
To drain the cooling system, bring the engine to operating
temperature, then open the petcock at the bottom of the
radiator or just remove the lower hose. Refill it with a
half-and-half blend, or refer to the chart on the coolant
container; it specifies the best mixture for your expected
temperatures. Run the engine while refilling the system,
and turn the heater on full to make sure the core fills
properly. Finally, inspect the radiator cap for
deterioration or leakage if it's the removable type, and
clean the radiator fins of bugs, leaves and other road
Modern cars equipped with electronic ignition go farther
between tune-ups and require fewer replacement parts than
older vehicles. But spark plugs and rotors do wear out
eventually, so you may want to check these parts if you
can't remember when they were last serviced. Carefully
remove one cable boot from a spark plug, and unscrew the
plug with a socket or plug wrench. (If you can't reach any
easily, defer to a professional.) Check the ignition end of
the plug for burned electrode tips, dark deposits or
wetness. If any of these are present, you'll need to spring
for a tune-up or diagnosis.
Next, remove the clips or screws from the plastic cap that
holds the ignition cables. Lift the cap to look at its
underside and the metal-tipped rotor beneath it. If there's
any sign of arcing or burning, get these parts replaced.
Unless you're comfortable doing tune-ups on conventional
and electronic ignition systems, it's best to leave that
work to a mechanic. Breaker-point systems require detailed
adjustments, and electronic ignition parts can demand
Air Conditioning and Accessories
Even though it requires a trained technician to service AC
systems, you can make some basic checks yourself. Examine
the belt for tightness and signs of wear. See if the
electric clutch kicks on when you slide the control lever
to the maximum cooling position. Inspect and tighten the
short copper ground cable on the compressor housing if one
is visible. With the exception of belt replacement and
screw tightening, any other woes are jobs for the pros.
Take a minute now to look at the belts that run the power
steering and the emission control air pumps. Replace them
if they're worn, and don't overtighten either one.
Tires and Shock Absorbers
Make this simple check: Push down sharply on the front
bumper, then on the rear one. If they return with a bounce
or don't rebound smoothly, your shocks are probably worn
out. You can replace them yourself for the cost of the
parts and several very dirty hours of your time. Or you can
have them replaced in about 20 minutes at a tire store and
pay about the same price if you catch a sale. Make your own
Tires play by the same rules. You should make a very
careful inspection of the tread and side walls. Wear in the
center of the tread or at the edges (over- and
under-inflation), uneven wear (imbalance), bald strips
across the face of the tread (wear indicators exposed) or
badly bruised side walls (curb impact) are all good reasons
to have the cause of the problem corrected and new tires
installed if the damage is serious.
Switch radial tires front-to-back, never side-to-side.
If there are no obvious problems, consider rotating the
tires yourself, for two reasons: One, they'll wear more
evenly if swapped around. (Radial-ply tires must always
spin in the same direction, and thus must be switched
front-to-back, not side-to-side; biasply tires should be
changed diagonally rear-to-front, and the front tires moved
straight to the rear.) Two, you'll learn through experience
how to operate the jack and tire tools, and you'll be
better able to loosen the lug nuts in an emergency if you,
rather than an impact tool, tightened them. Finish up by
inflating the tires, cold, to the pressures recommended by
the car manufacturer.
Exhaust, Brake and Drive Parts
At some point you're going to have to resign yourself to
getting under the car to complete your inspection. If you
can do it without jacking the vehicle in the air, great.
But you'll probably have to borrow jack stands or ramps to
gain access to the lowest parts. Always chock the wheels
that are still on the ground; never trust a jack alone.
First, examine the exhaust pipe, the muffler, the catalytic
converter (it's smaller) and the tailpipe for holes or rust
spots. Check the pipes for tightness and draw up on the
hanger clamps if needed. Be especially critical of the
gasket where the exhaust manifold joins the header pipe
(right at the engine).
Next, run your eyes along the path of the brake lines and
look for visible leaks. Check the fittings at the wheel
backing plates, too. Keep your eyes open for kinks or flat
spots in the lines. Trace the parking brake cables, and
lubricate them and the guide pulleys with silicone spray.
Finally, on rear-wheel-drive cars, check the universal
joints by rotating the drive shaft back and forth and
shaking it sideways. There should be no more than a
fraction of an inch of play besides what's offered by the
gear train. Any problems with these major systems should be
brought to the attention of a professional.
Don't Leave Home Without . . .
Tools, silver duct tape, a functional flashlight, a tire
pump, work clothing and a spare set of keys (to be carried
by another member of your family, not taped beneath your
car somewhere) will be blessings—if it turns out you
need them. If you don't, consider your self a great deal
luckier—or perhaps better prepared—than those
thousands of unhappy folks stopped at the side of the road