Troubleshooting Your Malfunctioning Angle Grinder

A man uses an angle grinder.

An angle grinder can prove to be a useful piece of equipment if you do a lot of do-it-yourself projects. However, the value of the tool goes out of the window if it fails to work properly. It is therefore beneficial to know how to find and rectify any faults that may arise.

No Power

If you switch on the angle grinder and nothing happens, the problem is likely to lie with the power supply. When it comes to an electric powered grinder, they can either be driven by batteries or by the mains supply. Check the batteries to ensure that they are fitted properly and haven't died. Replace them if necessary. For a corded grinder, check to make sure that the cord and plug have not sustained any damage. Replace the fuse if necessary. Check that there is a sufficient supply of gas, or air for gas, or pneumatic grinders.

Slow Revolutions

The benefit of an angle grinder comes not only from the surface of the disc, but also from the speed in which it spins. Where the wheel becomes stiff or loose enough to prevent it from spinning properly, it will no longer work to its full potential. Check how the nut is attached to the center spindle that holds the main wheel. Use a pair of pliers or a wrench to tighten it if it is loose. Clean the components of the center spindle if required and use a little lubricating oil to keep it moving.


Although the normal use of an angle grinder will produce sparks and flying particles, you should be concerned if smoke is created during operation. This could be caused by the wheel becoming clogged due to a build-up of debris and rust. If you do notice smoke arising from the grinder, immediately switch it off and disconnect it from the power supply. Remove the wheel from the spindle to give you access and clean all the components before trying it again. In addition, you must ensure that the size and type of disc attached to the grinder is the correct one for the task. Similarly, an excessive amount of sparks should be investigated to ensure it is not the sign of a greater problem.


Every type of grinder is going to make noise, but there can be times when it makes a different or louder noise than it normally does. Where this is the case, it can be a sign that it is working too hard. Make sure the power supply is adequate and doesn't leave the appliance struggling.


As with any electrical appliance, a certain amount of heat will be produced by an angle grinder while it is in use. However, if it gets too hot to comfortably hold, this should be taken as a sign of a fault. If the heat has come about after using the appliance for a significant period of time, turn off the appliance and rest it for a while. Check how quickly it cools down and whether the same level of heat comes from using it for a short period. Alternatively, check the motor to ensure there is not a fault with it.