It's been a pretty rough week for a lot of people due to the weather and our Kashy mechanics have already seen a number of very wet cars that were submerged in flood waters.
Whether the water came up around a parked car or your Hyundai Getz was doing its best impersonation of a small watercraft, water and cars never mix well.
Much like most electronic devices, modern cars are designed to handle rain and the occasional puddle but not necessarily full submersion. While it would theoretically be possible to make a car entirely waterproof, it would be an expensive fix for an infrequent problem.
So, what happens when a car floods?
The first issue is getting water in the engine, gearbox or other mechanical components. When this occurs water mixes with the oil and fuel and can cause a lack of lubrication, heavy misfires, damage to the pistons, connecting rods and piston rings and can even hydro-lock the engine entirely (a situation where a hydraulic fluid i.e. water locks the engine as it tries to turn and causes massive failure).
The second and most common issue (and by far the more important one in most cases) is electrical failure. While water in engine components might cause an instant failure, water ingress into the electrical systems can cause massive immediate cost and never ending gremlins for the rest of the cars' life.
This all loops back to the design of the cars to begin with. While the systems are meant to withstand some water, many of the connectors rely on small rubber seals which don't hold up when submerged. The water sitting in these connectors can cause everything from short circuits to long term corrosion and means that many of these cars need wiring harnesses and the computers replaced to be reliable again.
What can you do as an owner though?
Our first bit of advice is don't start any car that's been in water until it has been properly looked at. Doing so can cause enormous amounts of damage if the engine is 'wet' and can electrify short circuits which can cause fires or damage computers.
After that, the best advice we can give is to call your insurance.
Even if your car is in fair shape at the moment (and is starting, running and driving just fine), most insurers will classify any flooded car as an immediate write off due to the potential long term issues. Even if they don't write of the vehicle immediately, insurance assessors are trained in finding damage related to all sorts of weather events and will be able to decide if the car is repairable and what the best way to repair is.
If you don't have insurance, the best thing you can do is call a mechanic as soon as possible. A mechanic will be able to look over the car and decide the best course of action. Quite often this will include getting the motor started and allowing the car to dry out fully before going over it with a fine tooth comb.
While it might be a good idea to remove the water yourself to get a head start on the drying process, you have to remember the vehicle batteries can electrocute you.
All in all, being flooded is almost always an end of life event for a car which is a real shame.
If you have any questions about this blog post, would like a second opinion from a mechanic or would like to find an honest mechanic in Brisbane, check out Kashy here.