Steps for Dealing with Water Damage

Steps for Dealing with Water Damage

Last Updated August 8, 2023 | Meghan Drummond

Water can get into your engine via a variety of entry points. Whether you’ve just made it through a flood, went off-roading through a puddle that turned out to be a lot more sizeable than you imagined, or even just left your gas tank open during a rain shower.

Your engine just isn’t built to deal with water, even if you drive an off-roader like a Jeep. This is why snorkels are such a popular accessory and are something to consider if you really enjoy the experience of water fording. Snorkels run from your air intake up and over the windshield of your car, almost exactly like how a snorkel would work for a diver.

Regardless of how it got there, if you suspect that your engine may have water in it you can do a few things to reduce your chances of getting hydrolocked, which can destroy your engine.

What is Hydrolock?

In an internal combustion engine, hydrolock occurs when there’s water inside of your engine that makes it to the combustion chambers. This creates pressure that prevents the pistons from being able to move the way they should. Despite the “lock” occurring in the engine due to water, the rest of the engine keeps moving as it normally would, which causes the engine’s components to break apart.

The damage seen from hydrolock is similar to the engine damage that you might see from overrevving an engine or from a blown head gasket. Essentially, the cylinder heads, crankcase, and connecting rods can all break apart from the water pressure being exerted on them. In some cases, engine blocks have cracked under this pressure as well.

What To Do To Prevent Hydrolock

If you have a reason to believe that water has entered your damage, then you should check your engine for water damage in advance to turning it on, which may save it from serious damage.

The first step will be to disconnect the battery from your car and to set it somewhere dry. This is a good first step for any engine work, especially for any engine work that may involve hidden pockets of water, for fairly obvious reasons. Then, you’ll want to dry everything on your engine that you can reach externally before examining internal components.

Fluids are easiest to check. Because most of the fluids in your car don’t react well with water, you’ll be able to notice the symptoms of water damage almost instantly. Most fluids will have major consistency changes, or you’ll see a thin layer of water on top.

Two of the easiest, and most important, fluids to check are your oil and transmission. For the oil, if you see droplets of water on the dipstick or the quantity of fluid is well over the “full” line, then it’s probable that water has gotten into your oil.

Transmission fluid turns a strawberry pink after being exposed to water. Though most people are initially worried about their engines, transmissions are actually more likely to be damaged by substantial quantities of water. This is due to the intricate gears that operate inside of a small area and can’t withstand additional water applying pressure.

Perhaps the most challenging fluid to check is also critically important. You will also need to drain some of the fuel in your car to check for water. If there is water, you’ll need to drain the fuel tank, the fuel lines, and the fuel filters. Though this is time-consuming, it is a crucial step in preserving your car’s engine.

All contaminated fluids will need to be completely drained and replaced before you turn the key.

off-roader drives through a creek

A non-fluid component that needs to be checked is the air filter. It should be clean and dry. If there’s any evidence of moisture, go ahead and replace the air filters. It’s an inexpensive replacement cost that can save you a lot of money. If you have a reusable air filter, you can clean and reoil the filter to save money on a replacement.

One check that’s slightly less easy but can still offer important information is pulling your engine’s spark plugs. Once you’ve removed the spark plugs, you can manually rotate the engine’s crank until you can see the top of the pistons and check them for evidence of water.

You can also check the fuses of your car to see if there’s any obvious sign of external damage to any of them. Fuses that have been water damaged tend to have obvious physical defects. These are easy to replace, and if you replace them prior to turning the engine then it’s unlikely that you’ll cause damage to your engine if there hasn’t already been any.

If something doesn’t look right, then it may be time to get the vehicle towed to a mechanic unless you’re comfortable doing the work yourself. Even a little water sucked into the engine can cause serious damage.

Once you are sure you’ve replaced any fluids that have been damaged by water, checked the air filter, the pistons, and the fuses, it’s time to try to turn your car on. Hopefully, it turns on fine, at which point you can start to look for hidden flood damage that may need to be repaired.

External Water Damage

It’s a huge relief to find out that your car hasn’t been rendered nonoperational due to water, but don’t let your hunt for flood damage stop there. The first few hours after a vehicle has flooded are critical for fixing the long-term effects of the water on the vehicle.

Essentially, the faster you act, the less damage your vehicle will have.

First, you’ll want to check for external damage. This should be fairly easy to spot. Things like water inside of your headlight casings just seem annoying now, but it can cause your headlights to become dingy over time which leads to the light being less useful and can contribute to the headlights themselves having a shorter lifespan than they would have otherwise.

Another external area to check for damage are the wheel wells and undercarriage. Depending on how your vehicle was flooded, there could be significant debris trapped up underneath your vehicle.

In general, you’ll want to wash the exterior of your car after water damage, but this is especially true if it was salt water or brackish flood water that your vehicle was exposed to. Both of these can be very corrosive and cause substantial damage to areas of your car like the rocker panels, which are notoriously susceptible to rust.

When you do wash your car, using wax or applying a ceramic coating can help to prevent saltwater damage in the future.

A red Jeep water fording

Interior Water Damage

If water enters the interior of your vehicle, you’ll want to work quickly to eliminate standing water and reduce the possibility of mold developing. Mold can be very dangerous to breathe in, and in the fabric-covered, frequently warm, and newly wet interior of your car, mold will thrive.

If you have access to a dry vac, you should use that first. Dry vaccing can remove a good deal of the excess water in a car’s interior. Carefully vacuum out the car and pay close attention to the corners and underneath the seats, which are areas where water is likely to collect. Another area that sometimes takes on water during a flood is the glovebox. You’ll want to take extra care to clean this out, or at least check on it.

If you don’t have access to a dry vac, you’ll need to use a little more elbow grease and a whole lot more towels to get the water out of your car. Cloth, especially microfiber, towels are significantly better than paper towels in this instance since they are more durable, more absorbent, and less likely to leave wet bits of lint behind. Cloth is also easier to shimmy up into the frequently forgotten parts of your car’s exterior, like the door jambs, which collect water.

Pressing down on the towels to get them to absorb water is preferable to rubbing. Pressing will draw the water out, but rubbing will just tear up the fibers of your interior carpet needlessly and rub dirt in.

Once you’ve gotten all the water you can dry up with towels, it’s likely the inside of your car will still feel slightly damp. If you have access to a garage, you should park your vehicle inside and open all the doors and trunk. If you have dehumidifiers or fans, you should bring those into your garage will help speed up the process. Improved air flow is a great way to decrease drying time and also help to keep your car from developing any mildew smells.

It’s important to get the inside of your car dry as quickly as possible in order to avoid mildew and other types of mold and fungus. Though mold and fungus don’t sound serious, they can both cause serious illnesses while slowly eating away at the interior of your car.

If you don’t have access to a garage, you can use moisture-absorbing materials to draw more of the moisture out. Baking soda is particularly good for this and will help to reduce any bad smells that may linger. You can mix baking soda and white vinegar to create a spray that is especially helpful for smell reduction. You may need to get your upholstery shampooed in order to clean out any unsightly stains.

Red Jeep drives through puddle.

Next Steps

Unfortunately, even if you’ve done everything exactly right, you may still have issues. Water and electricity are not friends.

It’s possible the electrical components of your car will be fried and need to be replaced.

If you are considering getting your car fixed or replaced by insurance, it is critically important not to remove any electrical components or boards without first talking to your insurance adjuster. Even though you’d maybe expect that they’d appreciate a car enthusiast doing everything they could before calling, you may actually be voiding your insurance policy.

If you’ve done all of the above steps and your car still isn’t turning on, it may be time to make some hard decisions. Insurance companies do total out vehicles damaged by flood water frequently because of the damage that water causes and how costly it can be to fix. Obviously though, if your car has sentimental value or isn’t replaceable due to modifications you’ve made or its rare nature, then you’ll need to look at repairing individual components.

Checklist for Water Damage

By acting quickly, you may be able to save yourself from having to deal with the headache of hydrolock or interior mildew. Approaching your car methodically and following a clear process will help to make sure that you don’t forget a step.

  • Do not turn the ignition before checking under the hood
  • Check transmission fluid and oil for traces of water
  • Check air filter
  • Drain fuel to check for water
  • Check console and glove compartment for mud and debris
  • Wipe down metal inside car
  • Check headlight casing for excess water
  • Wash car’s exterior quickly and thoroughly
  • Get up standing water with a dry vac or towels
  • Air out car
  • Use moisture absorber like baking soda
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