Como reparar un motor Siemens de 3/4 hp que al arrancar lo hace sin fuerza y se bota el protector

🔧 Repair of an electric motor that starts slowly and blows fuses | Complete step-by-step diagnosis In this video, I show you how to diagnose and repair an electric motor that is experiencing trouble starting. The owner brought it to the shop because it sometimes stalls, other times it seems to want to work, but it won't start properly. If you're interested in learning how to detect the fault, what tests to perform, and how to fix it without replacing unnecessary parts, stay until the end. Let's get started! 🧪 INITIAL TESTS: What's happening with the motor? I connect the motor using alligator clips to observe its behavior. Without load, the motor starts but with little power. I simulate effort as if it had a pulley or a solenoid, and I notice that it can barely turn. The clutch is working correctly: it opens and closes as it should. This indicates that the problem may be in the capacitor or the starter coil. 📏 CAPACITOR CHECK: Is it within range? I use a multimeter with a capacitance function to measure the capacitor. Before testing it, I discharge it to avoid short circuits. When I disconnect it, I notice it's loose and has leaked acid: a clear sign of damage! The capacitor indicates a range of 400 to 480 microfarads. When I measure it, it barely reads 58 µF: well below the minimum. I get a new capacitor, clean the area, and install it to test the motor again. ⚠️ POWER CONSUMPTION PROBLEMS: Why does the thermal protector trip? When I leave the motor running, it shuts off and the multi-contact thermal protector trips (15 A). I clean the data plate to verify the nominal power consumption. The motor operates at 127 V and should draw around 12.7 A. If it draws more, there is an internal problem. Although the clutch opens and closes, the points are stuck together, which can cause overheating. There may also be damage to the starter or starter coil. 🔍 DISASSEMBLY AND INTERNAL DIAGNOSTICS: What's Wrong? I disassemble the engine to check the clutch and coils. I use a needle multimeter to test the points. I detect that they are stuck together, which may have caused the capacitor to fail and damaged the coils. The points must be properly removed to avoid overheating. I suspect excess sawdust, due to the woodworking environment, is causing the problem. 🧼 DEEP CLEANING: Removing the Sawdust I remove the rivets from the point to completely disassemble it. I use a vice and a bit to remove the rivets without damaging the part. Upon opening it, I confirm it's full of sawdust. I clean all the internal parts, including the caps and contacts. I use a utility knife to carve the points and remove burnt residue. I reassemble the system, riveting carefully to avoid damaging components. 🛠️ REASSEMBLY AND FINAL TEST: Did the repair work? I recommend the owner perform frequent maintenance, especially for wood dust. I replace the cap, taking care not to let any wires rub against the rotor. I assemble the rotor in its correct position, aligning it with the capacitor. I tighten the X-shaped screws to ensure the shaft rotates freely. I install the new capacitor and connect the multimeter to check the power consumption. The motor starts correctly and the thermal protector no longer trips! ✅ CONCLUSIONS AND FINAL TIPS The main problem was the excess sawdust that was keeping the contact points stuck. This caused the capacitor to burn out and the motor couldn't start. It was repaired without having to buy a new contact point, just by cleaning and adjusting it. This type of preventative maintenance is key to prolonging the motor's lifespan. If you work in dusty environments, such as carpentry, check your equipment periodically. 📌 If you liked this video, don't forget to like, share, and subscribe for more content on appliance and tool repair. Your support helps us continue creating educational and practical content for everyone looking to learn and save. 💬 Do you have questions or would you like me to repair a specific piece of equipment? Leave them in the comments. See you in the next video!