Do Your Servo Motors Look Like This: A Case for Standard Reconditioning

How Standard Reconditioning can vastly decrease the odds of a catastrophic breakdown

The machine environment can be a caustic one, with all kinds of opportunity for contamination to spew onto a servo motor.  Though your system and servo’s may be running fine, it’s only a matter of time before a buildup of contaminates (such as cutting fluids and metal shavings) will eventually creep inside the bearings and the stator and make a motor vulnerable to a catastrophic breakdown.  Contamination in the encoder and brake assembly due to improper maintenance is also common.  

Catastrophic in the sense that you are nearing a deadline and you must finish a run on a part for an important customer when suddenly your servo stops working.   Catastrophic in the sense that you are past a quick recondition and bearing change and instead in need of a full stator rewind and/or major machining work to correct a shaft on your servo motor.  These and other scenarios can be avoided.

A quick, standard recondition is what we would like to focus on, with timing being everything.

If there is a build-up of contamination that has been going on for quite some time,  or you can just begin to hear a noisey bearing, as maintenance personal,  you may want to consider a recondition the next time your machine is off-line, whether it be for a few days or a couple of weeks.


What is a Standard Recondition?

A standard recondition is when a servo motor isn’t critically damaged while in use, but still has wear and tear that needs to be corrected.  We come to this conclusion after all testing is completed and the motor is electrically and mechanically good:  Surge test, Megger test, Back EMF (electro-motive force) test to electrical integrity, mechanical tolerance checks, torque test (if the servo motor has a brake), testing of the feedback device.

servo motor testing during repair

Surge testing a servo motor.

Testing during servo motor repair.

Megger testing for ground.

Testing for servo motor recondition.

Back EMF Test for rotor.

testing during a servo motor recondition.

Verifying encoder counts.







Fanuc servo recondition

Scott power washes contaminated servo stator to get rid of heavier contamination.


During the next step in reconditioning, the motor is then taken apart, (rotor, stator, end bell caps, feedback, connectors, brake, etc.) and if the contamination is severe, the rotor and stator will be power washed first (Above) and washed a second time in a parts washer.  They are then baked in the oven overnight.

Servo Repair and recondition.

Assembling a servo motor with new bearings and seals.

Fanuc servo repair

Closely inspecting windings, leads, and thermals.

Fanuc A06B alpha-i servo motors

Applying sealant to keep out moisture and contamination.

Finished Fanuc servo

Reconditioning on this servo motor is complete!








When assembling the motor, the stator windings are given a layer of spray insulation; all seals will be replaced; connectors are replaced using American made connectors, which have an improved sealing mechanism that is glued instead of press fit. This makes the internal parts less susceptible to contamination, which is a leading cause for breakdown.  We also replace the bearings with new, high performance bearings.  When assembly is complete, it is fully run-tested for 2 hours with the appropriate amplifier or drive in a closed-loop system.  All of these things are done during every recondition-repair to increase longevity of the motor, which increases the uptime of your machine.

The Value of this Type of Preventative Maintenance

With preventative maintenance being a part of most company budgets, a standard recondition on your servo motors is a small investment and can save you critical downtime and lots of money, and even customers.   Since servo motors drive your machines, and in a sense, your entire business, investing in this type of predictive maintenance makes sense.


Repair Zone Can Help

Your machine or robot goes through hundreds to thousands of cycles per hour, and your servo motors power all of them.  At some point, a breakdown will occur.  The environments in which a servo motor lives can be filled with contaminants, which will speed up this process.  Our servo motor repair team can help you to drastically reduce your machine’s downtime with a standard recondition of your servo motor. With over 11,000 servo motor repairs under our belt, and 30+ years of doing it, our experience outweighs the competition.  Send your servo motors to Repair Zone for a quick, standard reconditioning today.  Or, if a catastrophic breakdown has occurred, we can provide more in-depth repair services as well.  You can also exchange your servo motor with one of our remanufactured units for faster service.

Frequently serviced Brands:  Allen Bradley, Fanuc, Indramat, Kollmorgen, Baldor/ABB, Modicon, Siemens, Yaskawa, Reliance


More information about Repair Zone:  Housed in a brand new facility, our servo repair lab performs entire repair in-house, including machining and rewind.  We average 3-5 days to get your motor back to you, emergency turnaround available.  Faster than the OEM, and less than 30% cost of new, you can also exchange your servo with one of our 5,000 in stock, for same day service.  And if you have a critical machine, you can purchase one of our remanufactured motors, at 50% less than new, for an economical solution to keep one on your shelf.  We also do servo drive and power supply repair!


More in-Depth Repair Services

Winding: Repair Zone has been winding motors for over 75 years.  Winding an electric motor takes great skill and knowledge; we have the people that have both.  Our winding department is housed inside our 80,000 sq. ft. facility.  We make our own coils using the finest high-voltage, Nano-shielded copper wire available.

Once the stator is re-wound, we dip it in our state-of-the-art resin tank, which can handle up to 8,000hp motors.  We are committed to doing the best work in the industry.  From servo and spindle motors, fractional 3-phase motors to 6,000 horsepower, and any frame or rpm, we can wind it.

Machining:  As a full-service repair center, we have the tools to complete any job, under one roof.  Like our Machining Center, it houses several  lathes and CNC machine and other equipment to straighten, correct, fabricate, cut, and turn parts for repair and remanufacturing.  We have 4 full-time machinists at Repair Zone.  Our machining capabilities include:

  • Shaft repair
  • Remanufacture a new shaft
  • End bell and bearing housing machining
  • Full welding and Metalizing department
  • Braising
  • Cut P-ways


  • Modify field housings
  • Motor bases
  • Housings
  • Enclosures
  • Shaft extensions
  • Straighten or grind shafts

We are an EASA Accredited company, meaning we follow strict guidelines from our industry to uphold the highest stands for electrical apparatus and rotating equipment repair.

Start Recondition Repair

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