Is Your Milwaukee Grinder Not Starting? This Might Be Why

We may receive a commission on purchases made from links.

If you're moving into the more advanced sphere of woodworking or welding, a grinder is one of the essential tools you'll want to add to your workshop. After all, it's a highly versatile tool that will come in handy if you want to do more than just make straight cuts. It's also good for sanding, grinding, and polishing a wide range of materials, including metal, wood, fiberglass, and concrete. Given that almost every major brand offers either a single power grinder or several, you'll want to ensure you get a high-quality model that matches your needs.

For those who want to stick with a brand that has an excellent reputation, Milwaukee is often a popular choice. It consistently ranks among the best cordless grinder brands in the market. And this is primarily because its grinders are highly regarded for their thoughtful design, performance, and toughness. In fact, a product like the Milwaukee M18 Cordless Small Angle Grinder (which retails for $126 on Amazon) has a 4.8-star rating from over 2,000 customers. Many state that they love it for its ease of use, efficient power delivery, reliability, and powerful brushless motors

However, while Milwaukee grinders may have plenty of standout features, that does not mean they are immune to some of the most common problems affecting power tools. After some days or months of use, consumers report that they occasionally experience Milwaukee grinders not starting as expected.

Unfortunately, the dreaded chug of a Milwaukee grinder that won't kick into action is no doubt one of the most frustrating experiences DIYers face. And when this happens, it's always crucial you know the reason; it will help you diagnose the issue and get back to work as soon as possible.

Generally speaking, the first thing that comes to most of our minds when a cordless power tool won't start is a faulty or dead battery, and your Milwaukee grinder is no exception. The average lifespan of Milwaukee power tool batteries is roughly three to five years. But it may be shorter if you're used to subjecting them to harsh environmental conditions. So, as you can imagine, if your Milwaukee power tool battery is damaged or dead, it won't provide the kickstart needed to get your grinder running.

Collapsed or worn-out motor bearings can contribute to the problem, too. Luckily, your tool's motor bearings will often give you a few clues before the situation gets worse. Things like weird noises and motor jams are early warning signs that you need to replace the bearings. Besides that, your Milwaukee grinder may sometimes fail to start due to paddle switch issues. This normally happens because of dust buildup, which short-circuits the safety spring contacts.

When your Milwaukee grinder fails to start, you're always left with two options. The first is waiting while you seek professional repair. The second is fixing it yourself. Of course, Milwaukee grinders are quite complex. But there are plenty of fixes you can try without relying on professional help, especially if you have a bit of know-how, some tinkering, and a few essential tools in your garage.

For instance, if your Milwaukee M12 and M18 battery packs won't charge at all or hold a charge, it's best to purchase new batteries. However, you can also consider refurbishing or rebuilding your Milwaukee batteries, but keep in mind that there are some caveats. If you do it yourself, you could ignite a fire, expose your health to toxic chemicals, or void your battery's warranty. The best approach is to send the batteries to an authorized Milwaukee company that specializes in refurbishing them.

If the battery is still viable but can't deliver the charge needed to start your grinder, check the contact terminals. If they're dirty or corroded, use a wire brush to dislodge any solid particles that are interfering with the connection. For collapsed bearings, you can fix this by using the "paper hack," which entails disassembling the grinder and wrapping a paper around the outer ring of the bearing. However, though it might sound like a cost-effective solution, it's best that you think twice before rebuilding Milwaukee power tools at home. A single wrong move could permanently damage your power tool.