How to Repair a Bench Grinder：Motor Problems

Bench grinders tend to break down once in a while. Here are some of the more common problems and their solutions.

1. It doesn’t turn on
There are 4 places on your bench grinder that can cause this problem. Your motor could have burned out, or the switch broke and won’t let you turn it on. Then the power cord broke, frayed, or burned out and last, your capacitor may be malfunctioning.

All you have to do here is identify the non-working part and get a brand new replacement for it. Your owner’s manual should have instructions to replace most of these parts.

2. Too much vibration
The culprits here are flanges, extensions, bearings, adapters, and shafts. These parts could have worn out, got bent or just didn’t fit right. Sometimes it is a combination of these items that cause the vibration.

To fix this issue, you will need to replace the damaged part or the part that does not fit. Make a thorough investigation to make sure it is not a combination of parts that are working together to cause the vibration.

3. The circuit breaker keeps tripping
The cause of this is the existence of a short in your bench grinder. The source for the short can be found in the motor, the power cord, the capacitor or the switch. Any of them can lose their integrity and cause a short.

To solve this issue, you have to identify the right cause and then replace the one at fault.

4. Overheating motor
Electrical motors do get hot. If they get too hot, then you will have 4 parts to look at as the source of the problem. The motor itself, the power cord, the wheel, and the bearings.

Once you discover which part causes the problem, you will have to replace that part.

5. Smoke
When you see smoke, that may mean that the switch, capacitor or the stator have shorted out and caused all the smoke. When this happens, you need to replace the faulty or broken part with a new one.

The wheel may also cause the bench grinder to smoke. That occurs when there is too much pressure applied to the wheel and the motor is working too hard to keep it spinning. You either have to replace the wheel or ease up on your pressure.