Motor Repair

Motors are important components to hundreds of devices we use in daily life. This Set-It Guide on motor repair tells how a motor works, what often goes wrong, how to identify a motor problem, and what parts and tools you will need to fix it. It so gives simple pace-by-pace instructions for how to test an appliance motor, how to service a motor'south drive mechanism, how to service a motor'southward gears, and how to service a motor's fan blades. Motor repair may exist needed to complete electric saw repair, flooring polisher repair, food grinder repair, power tool repair, slide projector repair, small appliance repair, and more.

How Does a Motor Piece of work?

A motor turns electrical free energy into motion. Actually, information technology uses electricity's magnetism to attract, then repel components to rotate a shaft. You can attach fan blades, knife blades, wheels, or a dozen other components to the shaft to make useful devices. To proper name a few: blender, cassette deck, CD role player, coffee grinder, computer fan, computer printer caput, DVD player, electric tin can opener. . .you become the thought. These and hundreds of other functional gadgets rely on electric motors to give them motility.

Smaller appliances typically use what's called a universal motor. It's simple, efficient, and relatively cheap. It's chosen "universal" because it can run on either alternating electric current (Air-conditioning) or direct current (DC) ability. The part that stands still is called the stator and the rotating part is the rotor. It'due south as simple as that.

Some pocket-sized appliances utilise a variation chosen the shaded-pole motor. It works virtually the aforementioned as the universal motor, but is less expensive to manufacture so information technology typically goes into lower-cost, low-load, small appliances.

Larger appliances, as yous can imagine, require more power. Many apply a split up-phase induction motor to develop more than rotating power, called torque, than smaller motors can muster. Split-phase induction motors, also, take stators and rotors.

Smaller things, such as battery-operated appliances and tools, get their power from DC batteries so they are fabricated to run on direct current. They don't take much motion or torque, just they get the job washed in a small space.

Motor Repair

You can see the commutator and the rotor within this motor from a variable-speed food mixer.

What'southward the difference? Ordinarily it's price. Well-nigh manufacturers apply the to the lowest degree expensive motor that does the job. Fortunately, checking whether a motor runs or doesn't is about the same for whatever type of motor. Unless you're adventuresome, you probably won't dismantle a motor and replace components. If it works, you'll utilise it; if not, you'll recycle it.

Many motors include a bulldoze mechanism of some type that transfers the shaft rotation to another component. You tin ready or supersede bulldoze mechanisms also (see beneath).

What Can Go Incorrect with a Motor?

Motor Repair

Turning on and off the motor's brushes (left, top, and lesser) creates a magnetic field that makes the motor shaft rotate.

Though efficient, motors can work confronting themselves. A small problem can become a big i quickly and, soon, the motor is damaged beyond repair. Fortunately, most motors volition tell y'all–sometimes subtly, sometimes not–that they are having bug. Motors fire out and freeze up; they get noisy, overheat, and wobble.

Fix-Information technology Tip

Hearing noises that may exist a motor going out? Plow off the apparatus immediately. It may exist something rubbing confronting the moving parts or it may be a trouble in the motor itself. In either instance, the faster you catch information technology the easier it will be to troubleshoot and prepare information technology.

How Tin can I Place a Motor Problem?

  • If gears on the motor shaft wobble, the bearings may exist worn out or some of the moving parts may exist misaligned.
  • If you come across sparks inside the motor, the rotor, stator, or brushes may be worn or damaged.
  • If you lot odor a mild odor of hot oil, metal, or plastic, the motor is overheating and may require lubrication.
  • If you olfactory property a pungent, acrid odour, the motor's windings may be damaged.
  • If the motor is too hot to touch, something may be blocking ventilation around the motor.
  • If the motor makes a grinding noise, bearings may be worn out.

Set up-It Tip

Parts inside a motor rotate, so they require lubrication to minimize friction. Some motors have holes on them marked oil where drops of lightweight oil can exist added. Other motors have hard-plastic bearings that don't crave lubrication but may eventually wear out after years of use. Check the owner'due south manual for your appliance to determine what regular service the motor requires.

What Do I Demand for Motor Repair?

If you lot accept electrical experience and some advanced tools, you lot may be able to repair a motor yourself. Nonetheless, most consumers opt to test and, if necessary, replace the motor. You tin can purchase one through the appliance'south manufacturer or an aftermarket supplier.

One time you lot've disassembled the apparatus (run across the appropriate Fix-Information technology Guide), hither are the tools you'll need to test an electric motor:

  • Screwdrivers
  • Wrenches (standard and hex)
  • Multimeter

What Are the Steps to Motor Repair?

Test an apparatus motor:

  1. Motor Repair

    This hair dryer motor and fan can be tested easily using a multimeter.

    Make sure that the ability string wires are asunder from the motor. If it is easy to do, remove the motor from the appliance, though motors tin can be tested in place.

  2. To exam continuity (the flow of electricity) through the motor, set the multimeter on the RX1 (resistance times ane) calibration to measure resistance (in ohms). The multimeter's internal battery will send a small electric electric current through the motor's wires.
  3. Adhere one of the multimeter's probes to the motor'southward common lead, unremarkably white.
  4. Attach the other probe in turn to each of the other wires on the motor. The probe will check to see if it can measure the multimeter's input point at the output. A low or moderate reading (in ohms) means the component is okay. A cypher or infinite reading ways the motor's windings or another component has a short.
  5. If it tests faulty, supervene upon the motor with one of the same blazon, power rating, and size.

Service a motor's drive machinery:

  1. Tighten the setscrew that attaches the pulley or neckband to the shaft.
  2. Adjust the drive chugalug then it is not so tight it wears out the shaft nor so loose that it doesn't rotate with the pulley. If the belt is worn or damaged, supervene upon information technology.
  3. Check and tighten or supercede any reduction or worm gears on the shaft. Gears typically come in pairs and should be replaced every bit pairs.

Service a motor'southward gears:

  1. Detach the appliance to access the motor'south gears.
  2. Remove and inspect gears for obvious harm or wear and supercede every bit needed. Gears, especially, are susceptible to damage because many are fabricated of plastic that can break or bit.
  3. Reassemble and test.

Service a motor's fan blades:

  1. Disassemble the appliance to access the motor's fan blade.
  2. Remove, audit, and repair the fan blades. If not repairable, damaged fan blades should be replaced because they can spin unbalanced and potentially impairment the motor.
  3. Reassemble and exam.

Set up-It Tip

Install a new motor or reinstall the old motor in the verbal same way as information technology was removed, making sure that all wires are connected as they were originally.