Alternator Guide – Can Water Damage the Alternator Of A truck?

The alternator is a vital part of your truck that takes the mechanical energy from the engine and turns it into electrical energy that is stored in the battery. The electrical energy aids in the smooth operation of other electrical components of the engine. 

It is essential to understand how to maintain your alternator, and you should be aware of various issues that might arise and how to repair them. The alternator is one of the components of your truck that you can easily monitor. After reading this guide, you will understand what happens when your alternator comes in contact with water.

Is An Alternator Waterproof?

Regarding water and alternator, most truck owners always need clarification. Your alternator is not waterproof, and thus you must check it when it gets into contact with water. You will need to repair your alternator for it to function correctly. Your alternator may not be watertight, but it does not imply that it is resistant to water.

Bearing at the back of your mind how an alternator is built to function, it is almost impossible to be waterproof. A number of the alternators are air-cooled. They have an internal fan that draws air to cool the inner components. 

The non-drive end sucks air in while the drive end expels air from the alternator. Since your alternator is not waterproof, it does not mean it is not water resistant. 

What Happens When Your Alternator Gets Wet

You now know that the alternator is not waterproof or safe to expose to water. Here is what is likely to happen when your alternator gets wet. 

Exposure to too much water can damage the alternator of your truck. But a drop of water does not significantly impact your alternator. However, if you expose it to flooded water, it can turn nasty. Your alternator will get damaged when a good section is exposed to water. 

For an instance, its parts such as bronze and brass, are exposed. Such parts can endure severe damage when your alternator becomes damp. Such brushes are regularly lubricated to reduce wear and electrical arcing. But when the brass and bronze are submerged in water, the oil lubricating them will wear away, which can harm them.

When your truck is submerged, debris like sand can get into the alternator’s brushes, which makes them freeze and lose touch with your slip rings. 

Drying a Wet Alternator

When your alternator is wet, the brass and bronze suffer. You must clean it as soon as possible. Doing this will prevent further damage.

Consider spraying your alternator with CRC electric clean, then use it after 24 hours. Let your hood open for better air circulation. Doing this protects your alternator from damage.


An alternator is an essential part of your truck. It generates electrical energy for your truck. An alternator is not waterproof and has air openings that water can take advantage of to access the delicate inner parts. If you drove in a flood area, consider taking your alternator for a check-up to avoid further damage. 

4 Symptoms of Bad Alternator System in a Truck

In this guide, we will look at how to know when you have a bad alternator in your truck. The electrical system is an integral part of your truck, which is the source of entertainment, gives you vision at night, and enables you to signal other road users. The electric system will allow your wipers to work effectively in heavy rain. There must be a power source for all these electric parts to function effectively. The alternator is the primary power producer of any truck. As the name suggests, it changes the energy from the engine to that which can be utilized by the electrical parts of your truck.

The alternator plays the role of charging the battery of your truck, and it is connected to the battery, so the battery does not run out of power. The work the alternator does stresses it, and at some point, it breaks down. This guide will focus on some symptoms that will let you know if your alternator is faulty.

4 Symptoms of a Bad Alternator

The battery warning check light on the dashboard is the most common symptom of a bad alternator, sometimes your headlight will not be stable when put on. You may also hear a funny noise from the engine. Now you know the most common signs, having an in-depth look at them will cause you no harm.

Battery Warning Light

The appearance of a battery warning light on your dashboard clearly indicates that your alternator is faulty. How will the appearance of the battery check tell you that your alternator is defective? When your ignition is on, your battery’s voltage is over 13 volts. A healthy truck battery has 12 volts, which will shoot to 14.2 when the alternator charges it. When the voltage drops to 13 volts and the ignition is on, the battery check light will appear on your dashboard.

Dim Headlight

The headlights consume a lot of power, and thus they need a lot of electricity. When they receive adequate power, they will be very bright. As your truck runs, the headlights will consume the light on the alternator. A faulty alternator will not supply adequate power to the headlights, making them not light bright.

Battery Starts to Drain Faster

You will be charging your battery regularly, but it keeps draining even if it is still healthy. When you note this, the alternator could be faulty. A faulty alternator will supply the battery with inadequate power, and other electric parts of the truck will depend on the power from the storm, which will drain it very fast.

Funny Noise from the Engine

The alternator has bearings and spinning components that are metallic. If it experiences any physical damage, your truck will produce a loud squealing or banging nose. Faulty bearings mainly cause noise in the generator. You can easily spot your truck’s alternator from the engine bay, so you can easily open it and check the cause of the noise. This is one way of knowing whether you have a bad alternator.


The above four are some common symptoms of a bad alternator, knowing them quickly lets you know the right area to check if you experience any of these signs. This is something that most people do not keep in mind when doing regular truck maintenance.