By Joseph D. Younger

Joe Falco will never forget the lesson he learned about high water while working for AAA Emergency Road Service. He was responding to a call from a motorist who had wound up stranded after trying to navigate a flooded underpass in his car.

“I saw the car ahead of me get through,” said the motorist, “so I thought I could make it, too.”

After waiting nearly an hour for the water to recede, Falco finally managed to hook up the water-logged car and tow it out. The two men headed toward the repair shop. But they didn’t get far when they passed that poor soul who had braved the water first. His car had quit less than a block away. And there it sat—waiting for a tow, too.
The lesson?

“When it doubt, don’t take the chance,” says Falco. “It’s impossible to tell how deep the water is or, more important, how fast it’s rising.”

Sometime this year, between spring showers and summer gully-washers, you may come upon a section of partially flooded roadway and face the same decision: Turn around, or go across?

Before deciding, understand your car’s capabilities— and the possible consequences.

Take the Plunge?
Face it: cars aren’t boats.  The fact they have wheels should give you a clue. They’re simply not designed to handle much water.

“Naturally, the computer and electrical system are the most at risk from water and associated contaminants,” notes Falco. “And these are among the most expensive systems to repair.”

Besides sophisticated electronics, the low-slung, aerodynamic profile of many newer cars increases their vulnerability to high water.  Models with particularly low air intakes will sputter and stall in water as shallow as six inches.

Your ostensibly rugged SUV or pickup may not fare much better.
TV ads may show your vehicle splashing merrily through streams in the wilderness, but don’t think you can navigate flooded roadways without a care.

Even off-road vehicles boasting a fording depth of 20 inches or more, might still require transmission plugs and other special equipment to cross such deep water. Unless you’re absolutely positive that your vehicle has the right equipment and you’ve installed it properly, always regard high water warily. 

“There's a difference between being sprayed by water and immersed in water,” say Richard D. White, senior vice-president of the Automotive Aftermarket Industry Association, a group that represents parts suppliers and repair shops. “This is true regardless of whether it's a car or truck, SUV, or whatever. None of these types of vehicles is intended to be operated with their axles or other main components under water.”

Swimming to the Other Side
But let’s suppose you’re stubborn, ignored the advice above and driven straight into a big puddle, only to find water halfway up your hubcaps or higher. Now what?

If you’re lucky, you’ll make it to the other side before the engine stalls. At this point, experts suggest sitting tight a while. Keep the hood shut and hope residual heat from the engine dries out components. Or, on a warm, sunny day, lift the hood to dissipate moisture faster. Then try to re-start the engine.

If the engine turns over, you’re good to go. But drive away slowly with your left foot resting lightly on the brake pedal. “Riding the pedal” in this way will produce friction to dry out wet brakes.

Take the car to a qualified technician at the first opportunity, especially if you went deep enough to partially submerge the wheels.

“Water may intrude into the bearings and contaminate the lubricant,” explains White.  “Serviceable bearings may be cleaned, inspected, and re-lubricated. Permanently lubricated bearings may need to be replaced.”

On your way to the repair shop, listen for knocking, tapping, squealing, or grinding noises. These or other unusual sounds may come from the alternator, drive belt, starter, power steering, air conditioner, or suspension components—all susceptible to water damage.

“The most important thing is to have the noise checked out as soon as possible to determine its source and severity,” says White.

Glug, Glug, Glug
If you can’t start the engine, no matter how long you wait or how many times you try, you’ll need a tow. At the shop, a good technician will inspect all fluids (especially oil and transmission fluids) and pull the differential plug.

Water-contaminated engine oil looks milky or develops white foam on the fill cap. Ordinarily, diluted transmission fluid also looks milky or turns beige. But synthetic fluids used in some transmissions might seem milky, even without water present. Let a pro make the call.

Any sign of water contamination is bad news. For example, water in the oil pan will affect lubrication, which may lead to damaged bearings, camshafts, followers, and other expensive components, explains White.

The tech will also check the air filter for water, replacing it and changing the oil if it’s wet. The shop should replace any lights containing water, check brakes and seat brackets, and inspect the suspension for mud and other debris.

Meanwhile, you should check the radiator, undercarriage, frame, and bumpers for grass, mud, and other flotsam and jetsam. Depending on what you find under there, wash it off with a high-pressure hose or seek professional help.

Soaked carpeting, upholstery, seats, and trunk linings present another problem entirely. You can’t let them dry out on their own, explains White. Doing so simply invites mold, mildew, and nasty smells later.

“It means professional cleaning,” he says.  “Water is extracted from the carpet or upholstery, cleaned with the appropriate solution, rinsed clean and then dried.” Your repair shop or auto detailer can refer you to a qualified pro.

At the end of your adventure, you can expect your bank account to sink lower than your car did. Think about those dollar signs before you set sail.

One time, on time. Courteous, honest service: AAA Car Care Center offers maintenance and repair from a name you can trust. Visit AutoMarkCarCare.com for details and locations near you.