Are Brushless Motors Waterproof? (Hands-on Info)


No matter how you use your RC vehicle, the chances are that they may come in contact with water even with the utmost care. 

In fact, some RC enthusiasts fully submerged their RC vehicles in water without considering the possibilities of future repercussions, especially on fragile electronics like the brushless motor. Why? Some manufacturers advertise their RC models as fully waterproof right out of the box. 

This drives us to the question, is the brushless motor in the RC vehicle really waterproof? 

Can A Brushless Motor Get Wet?

The simple answer is that brushless motors are not fully waterproof. The sensorless brushless motors are, to an extent, water-resistant, while the sensored ones are not.

Due to their water-resistant nature, when your sensorless motor comes in contact with a wet surface or is fully submerged in water, it will still operate fine. Still, because they are not fully waterproof, you can’t fully submerge them in water without any mechanical wear and tear on the brushless motor. On the other hand, a sensored brushless motor comes with a solid-state magnetic field sensor board that is widely exposed to water. Once it gets wet, it rusts and wears out. 

which brushless motors are sealed to water

The sensorless brushless motors are sealed, while the sensored ones are not. If you have a sensored brushless motor, you need to make sure that they are sealed before going for a wet run. 

Sensored motors are typically vulnerable since they have sensors designed on top of them. Once exposed to water, the magnetic field of your sensors corrodes and damage. 

Its OK for a brushless motor to get wet

Technically, brushless motors can get wet, but you should avoid getting your sensored brushless motors in the water since they damage faster. 

The sensorless brushless motors can operate well in wet conditions. Still, you also need to avoid running in water as much as possible because the water in your brushless motor will contribute to the wear and tear on the motor, making you find replacement parts faster than its shelf-life. 

Can you waterproof a brushless motor?

Brushless motors, especially the sensored ones, can be made waterproof. However, this does not guarantee they will last long. 

RC hobbyists can make their brushless motors waterproof using dielectric grease.
Dielectric grease is a good sealing agent that helps you seal the sensor board of the motor. Make sure to apply the dielectric grease over the sensor before using the brushless motor in wet conditions. 

Will water destroy your brushless motor?

Water can find its way even in the smallest entrance, and since your brushless motor comes designed with a ventilation space, there’s a high chance it will damage by water penetration. 

In essence, water will damage the brushless motor. Why? It has three fragile parts: the fixed sensor, rotating magnets, and the rotating shaft. 

The brushless motor is designed with the senor permanently displayed on its surface. When the sensor is exposed to water, it rusts and loses its magnetic state; even if you try to use the motor the next day, it never works. 

On your brushless motor, the shaft is one of the easiest places water can penetrate due to the small openings on the double bearings. If you run your RC car in a lake or puddle, you’re sure to get small particles of dirt and sand in the bearings of your brushless motors, which can destroy them over time. Plus, when the bearings wear out, it can cause the motor’s rotor to touch the stator, damaging the motor if spun up. 

What to do when a Brushless motor got wet

As mentioned earlier, water on your brushless motor can cause the bearing, shaft and sensor to corrode. 

To avoid this, spray the motor down with WD-40 after it gets wet. WD-40 is designed to displace water. Alternatively, allow the brushless motor to dry thoroughly for a few days. Detach it from the RV vehicle, hang or stand the motor, so the water drains out from the ventilation holes in the front.


Sensorless brushless motors can survive in wet conditions. However, their mechanical parts can easily wear out if not maintained properly after being used in water. On the other hand, the sensored counterparts will become faulty when used in wet conditions since they are not sealed. The good news is that if you have a sensored brushless motor, you can make them waterproof by using dielectric grease on them before fully submerging in water.