What are the symptoms of water ingress in an electric motor?
3 Answers
The symptoms of water ingress in an electric motor can be observed from the following aspects: 1. Visible faults: The motor fails to operate, bearing damage occurs, noise increases significantly, and in severe cases, the coils may burn out. 2. Hidden faults: Parts of the motor may rust extensively, leading to magnetic pole short circuits and decreased insulation performance of the coils. The motor's current will continuously increase, secondary faults will keep accumulating, and eventually, the motor will need replacement. 3. Treatment methods: Remove the motor, dry it thoroughly either by heating or sun exposure, and remove any rust. Use the finest sandpaper to polish the rotor and stator to prevent friction, and inspect the bearings.
I've been driving electric vehicles for many years and have encountered issues with water ingress into the motor several times. Typically, the vehicle emits a buzzing abnormal noise, responds sluggishly when starting, or directly stops working, and warning lights may appear on the dashboard. Long-term water ingress can cause coil short circuits and rust, and in severe cases, it may lead to smoke or a burning smell, damaging the entire powertrain. During car washes or driving in rainy weather, water can seep in through poorly sealed air intakes. For prevention, I always ensure the motor seals are intact and avoid driving through deep water. If water has already entered, immediately cut off the power and send it for repair; don't attempt to handle it yourself, as this could result in higher repair costs. Regular inspections can prevent problems before they occur.
In the auto repair industry, common symptoms after a motor gets wet include stuttering during startup, unstable RPM, and sudden shutdowns. Once, a car owner drove through water, the motor got soaked, and the car stalled without warning. When I opened it up, it was rusted and moldy inside. Repairs can be tricky, possibly requiring part replacements, costing upwards of a thousand bucks. My advice: if water gets in, immediately disconnect the battery and try drying it with air, but the safest bet is to take it to a professional shop. Daily care should focus on moisture prevention—keep water away from the motor area. Small issues turning into big problems is common; early fixes save headaches.
