October 2, 2023 admin

What Causes Water Spots and How to Remove Them?

A friend invites you over to his house for a barbeque.
You arrive and have to park your car outside his neighbors with the lush green lawn.
The party ends late, and you drive home in the dark.
The following day the sun is shining, and then you see them.
Nasty white spots on the side of your car.
You run inside and grab a microfiber towel, but the marks won’t come off.
They are there glaring at you.
Last weekend, you waxed your car, so why do you have water spots?

All Water is Not Pure.

You would think that water sprinklers and natural rainwater would not be a problem. After all, it’s just water. Right?

You see, irrigation water, also known as hard water, has minerals that etch into the surface of your car’s paint.

What Exactly is Hard Water?

The simple definition is hard water is high in dissolved minerals, primarily calcium and magnesium.

You may have felt the effects of hard water. Have you ever washed your hands or shampooed your hair and wondered why the soap didn’t lather?

If hard water has a chance to dry, it seeps into your paint and leaves unsightly white spots on your paint that are hard, if not impossible, to remove.

Where Does Hard Water Come From?

Anything water-based that comes from the sky is classified as acid rain. This includes dew, rain, and snow.
These natural weather elements settle on cars and can cause significant damage when it comes in contact with a vehicle’s exterior paint.
The acidity in the water, which is a combination of nitric and sulfuric acids, can cause the paint and even the metal to weaken over time.
The truth is all rain is contaminated with some levels of acid. And more so if you live in a bustling metropolitan area.

You see multiple contaminants in the air blend with falling rain to create acid rain.

While some wax or sealant products can help reduce the damage that hard water can cause, it’s not a 100% solution.

However, what is not commonly known about acid rain is that it doesn’t need to rain for acidic contaminants to hit your paint.

What Does Acid Rain Damage Look Like on a Car?

Mineral deposits are spots of minerals that are left behind after the carrier has evaporated.

How Does Acid Rain Impact a Vehicle?

Damage happens when the acid material is left behind on a car’s surface after the water evaporates. According to the EPA, the acidic compound combined with other elements such as sunlight can be strong enough to eat away at the paint.
I know I was also shocked!
Vehicles with a clear coat are more vulnerable to the damage acid rain causes. That includes cars from the early 1990s.
Think of your clear coat as the car’s first line of defense against body rot that might otherwise require extensive repairs. A hazy, dull finish on a vehicle often signals apparent coat oxidation.
According to research conducted by the EPA, there will be “irregularly shaped, permanently etched areas” on a car’s surface if it has been impacted by acid rain.

How To Prevent Water Spot Damage

So, the best way to prevent water spots from happening is to make sure your vehicle is professionally washed to keep your car clean and protected. This will help to avoid acid damage rain can create.
Most importantly, make sure your vehicle is hand dried.
Also, completely cover your vehicle with a car cover or park your vehicle in a garage when precipitation is in the forecast.
That means if you accidentally park next to an irrigation system and the sprinklers have bathed your car, immediately dry your paint with a microfiber towel before the water has a chance to dry.

How To Remove Water Spots from Car Paint

  • If your car is dirty, wash your car and dry it thoroughly with a microfiber towel.

If the water spots are still there after washing your car, you need to get a little more aggressive. 

Before trying this step, make sure that your car’s paint is cool to the touch. 

  • Next, try a 50/50 mixture of distilled water and regular white vinegar. 

What Is Distilled Water?

Distilled water is steam from boiling water cooled and returned to its liquid state. Some people claim distilled water is the purest water you can drink.

All water- whether from a natural spring, artesian well, or regular tap- may have trace but safe amounts of minerals, bacteria, pesticides, and other contaminants.

Distilling rids water of all those impurities. It also removes more than 99.9% of the minerals dissolved in water.

Apply the vinegar/water solution with a spray bottle onto the affected area. Soak a microfiber towel with the 50/50 mix and gently rub on the affected area. The vinegar should break down the minerals in the water spots and make them easier to remove. Ensure you wash the area and dry thoroughly to remove the vinegar from the paint.
If the vinegar combination doesn’t remove all the water spots, try using an MDR.

An MDR is a mineral deposit remover, such as Stop Off from your favorite car care brand.
These products usually contain phosphoric acid, more robust than vinegar with pH levels lower than 3. MDR products are more powerful against calcium carbonate and other minerals.

Safety Warning: Dealing with stronger chemicals, we always recommend wearing gloves and safety glasses. Rinse hands thoroughly when done.

Put some on your microfiber towel or applicator and rub it onto the body panel for 30-60 seconds. Then, wipe it away with a clean towel and check the results. If the water stains are gone, rinse the panel thoroughly with water to remove all the excess acid.

If faint white water spots remain, try using a clay bar.

The Clay Bar Method

A clay bar can help remove mineral deposits and stuck-on dirt and grime.
Claying should always come after giving your car a good wash and drying it thoroughly.
Wet the surface with soapy water and rub the clay bar on the affected area. It should remove the calcium carbonate from the area causing the spots. However, it cannot do anything about the stains soaked into the paint’s pores.
Therefore, this method is the most effective if you have previously applied a nano-ceramic coating, ceramic spray, sealant, or wax to the body.

Your Final Option is Compounding and Polishing

If hard water deposits have baked too hard into your paint, they could have left micro-cavities behind after using the above methods to remove them.
These dimples will collect water and contaminants every time the car gets wet, worsening the problem over time causing your paint to look dull.
The best way to remove these etchings is to polish the clear coat to flatten it out.
If the layer is too thin, you’re looking at an expensive sanding down of the affected area and respraying of the clear coat at a professional correction paint shop.

Here is What You Can Do to Protect Your Car’s Exterior Paint

As you’ve probably experienced, keeping hard water and acid rain off your car is exhausting.
Paint sealants and waxes will offer some protection against mineral deposits.
But even the best formulas will quickly give in under chemical attack, making them ineffective against acid rain and other environmental pollutants.

How Ceramic Coating Protects Your Car from Acid Rain

The best way to avoid water stains is to coat your car with protective layers of ceramic coating.

Industry-grade ceramic coating is a chemical polymer solution applied to the exterior of a vehicle to protect it from external paint damage.
Ceramic coating offers good protection to the car’s surface. The nano-coating can protect the vehicle from scratches, dirt, and chemical contaminants.
Paint correction through buffing is recommended before applying a ceramic coating for optimal results.

So, the best way to avoid water spots is to apply a ceramic coating. Whether you do it yourself or have a dealer do it for you, this is by far the best – and most cost-effective way of reducing damage from acid rain.

Want to learn more? Give us a call at 209-718-7000

Or contact us through our website.



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