Before we talk about how to replace carbon brushes in an angle grinder. But why do we need to replace them in the first place? The main reason! If your angle grinder has lost power, is sparking more than usual, or has stopped working entirely — worn carbon brushes are usually the cause. The good news: replacing them takes about two minutes and costs almost nothing.
Depending on your grinder model, you’ll run into one of two designs. The process is slightly different for each.
How to Replace Carbon Brushes in an Angle Grinder – Video Guide
Type 1 — External Cap Access
Some grinders have carbon brush caps visible on the outer body — no disassembly needed.
- Unscrew the cap on the side of the grinder body.
- Pull out the old brush.
- Insert the new brush in the same orientation as the old one. Direction matters — inserting it the wrong way causes premature wear.
- Screw the cap back on.
- Repeat on the other side.
That’s it. Your grinder is ready to use.
Type 2 — Housing Access
Other grinders require opening the housing to reach the brushes. It’s a few more steps but still straightforward.
- Open the grinder housing.
- Locate the carbon brush holders inside.
- Unscrew the brush holder and disconnect any attached connectors.
- Remove the old brush — it’s usually held by a push lock, so a small screwdriver is enough to release it.
- Insert the new brush in the same orientation as the old one.
- Reconnect the connectors and reseat the holder.
- Repeat on the other side, then reassemble the housing.
Always unplug your grinder or remove the battery before opening the housing or touching any internal components.
How to know when brushes need replacing: Most brushes have a wear line marked on them. If the brush has worn down past that line, replace it. Don’t wait until the grinder stops completely.
If you’re new to angle grinders, the carbon brush replacement is just one part of keeping the tool running well. For everything else — discs, safety, cutting and grinding technique — the full beginner’s guide covers it all.→ How to Use an Angle Grinder Safely — Complete Beginner’s Guide
