How To Repair A Flooded Car

Water damage is a lot more complicated than you realize.

bySteven Lang|
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The used car business has a lot of dirty secrets.

Odometers that can be rolled back with either a computer or basic tools. Replacement body parts that are made out of cheapest of metals, plastics, and fiberglass. We even have mechanical components that are designed to fail after a certain point, so that the purchaser gets to revisit their local auto parts store every few years.

These three areas of the business have already been through a rise and fall. Odometer fraud is a lot less common these days. Substandard body parts aren’t quite as common as they were back when certain insurance companies promoted their use, and the engineered-to-fail starters and alternators have been replaced by better quality parts thanks to online reviews that out these products.

However there is one area of the used car business that has remained a mainstay for decades – flooded cars. A little over a third of the vehicles that were impacted by the recent flooding in Houston did not have comprehensive insurance. These cars have no insurance company payoff that will enable that car to be totaled and sold at a salvage auction.

Instead, many of them will simply remain a part of the automotive landscape. Many that are owned by used car dealerships will be sent off to wholesale auctions that are far away from Texas so that the dealer can get back any money that they can. More than a few of flooded vehicles owned by individuals will be traded-in to dealerships. This will cause a nice healthy bump in the number of new cars sold in the state of Texas, but those vehicles too will be sent off far, far away. When I traveled around the country liquidating vehicles for Capital One Auto Finance, we saw swarms of vehicles from Louisiana, Alabama, and Mississippi find themselves inland at auctions as far away as Chicago. However the biggest group of these vehicles that are not riddled with saltwater will stay right in Texas for one simple reason.

A flooded vehicle can be repaired by an experienced mechanic, not you! I am intentionally leaving steps out because the process of repairing a modern car that has been flooded is far more complicated and the dangers are real.

The owners of these vehicles in the times to come will more than likely deal with constant electrical issues and I would put good money on more than a few of these vehicles experiencing catastrophic failures that knock them completely out of commission.

The bulk of these vehicles will be repaired, regrettably, and the way to do it is not exactly rocket science.

This is basically what you should do with the engine.

  1. Check the oil dipstick to see if there is any water contamination.
  2. Loosen oil drain plug and release any water
  3. Remove the spark plugs
  4. Change the oil and filter
  5. Crank the engine with the plugs out – be sure that all water sprays out of the engine.
  6. If there was water in the engine, spray a little oil in the cylinders and crank some more.
  7. Now replace the spark plugs and try to start it.
  8. If the engine runs, let it run a few minutes, shut it off, and check the oil again.
  9. If the oil is cloudy or milky at all, change the oil and the filter.
  10. If the any water got into the gas tank, it must be drained before you crank the engine or water will be pumped into the fuel system and cause a lot of trouble.

If the car got soaked in salt water DO NOT DO ANY OF THIS. It’s toast. Don’t even try to save it. Just pay a junkyard to pick it up and walk away.

If your fuse box, control units or modules were submerged in water they will also need to be replaced, and prices for these components tend to spike right after major hurricanes. If you don’t replace them, these particular electronic items will be prone to failure over time, even if they operate right now. The same is true with your wiring harnesses and battery cable connections.

Airing out the interior will take a lot of time and effort, and you will want to remove all your body panels and interior trim components as well if the car was submerged up to its doors. In certain cases you will need to strip out the entire interior, including the seats and trunk area, and get a new carpet installed. This may be worthwhile to do since certain fuses and wiring will be present in the lower portion of your interior. Inspect those for water damage and let these air out.

If your mechanic doesn’t have any experience working with flooded vehicles, the car may not be worth trying to save. In fact, most mechanics won’t touch these vehicles with 30 foot poles due to liability issues. As for you, very few car owners have ever done any major work to their vehicle and electrical issues will be your greatest enemy in the times to come. If you want to overcome your fear of working on a car, this is a great time to practice basic wrenching with the realization that you should never operate this vehicle ever again.

So do yourself a favor and don’t put it back on the road. Flooded cars can be rolling deathtraps. I’m leaving plenty out because I frankly don’t want you to do anything other than find another car that doesn’t have flood damage. The United States currently has over 260 million vehicles that fit this category and you should be available to find a good one in the times to come.

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