Introduction: Make an Electric Motor Run Again

Picture of Make an Electric Motor Run Again

You have an electric motor designed to run on alternating current, but it does not run. What can you do yourself? This Instructable concerns a triage procedure for getting your capacitor start motor running again in a series of easy and logical steps.

I am assuming you have a single phase 1/4 or 1/2 horsepower motor, even possibly up to 1 horsepower. It may have one capacitor, but there may also be two. The motor's design may be capacitor start, or capacitor run. These types of motors are what you will find in most home and workshop applications. Special purpose industrial motors (DC, three phase) will have some differences and I still know nothing about them.

The most common cause of HVAC failure during the hot summer is a motor capacitor. (Your air conditioner does not run, but just hums with a buzzing sound.) Knowing that, you can use what you find in this Instructable to check your system and replace the capacitor even before it fails.

Note: This Instructable is written to share some helpful things I learned, as well as some tools and resources you will find helpful. The purpose is to give the reader enough help to make some careful tests and solve some basic problems. Please do not ask me to diagnose your motor from a distance and tell you how to fix it. I am not equipped to do that. Get a book like the one I bought (see step 6), seek out some articles on the Internet, and watch some videos. Then make some careful tests in a logical order. Reason things out. Be prepared to renounce your assumptions. Be patient. You may get your motor running again, too.

Materials-

  • Bearing grease
  • 16-3 power cord and plug (if needed to replace an old cord)

Tools-

  • Sharply pointed round prying tool (for lifting bearing seals)
  • Hammer, punch, and flat surface (for smoothing bearing seals before reinstalling)
  • Soldering gun and solder
  • Screwdrivers
  • Nut drivers
  • Volt-Ohmmeter
  • Capacitance meter (optional, but nice to have--See step 5.)

Step 1: Spin by Hand

Picture of Spin by Hand

Turn the motor shaft by hand. Does it turn freely enough to run? There will always be a little drag, but the shaft should spin relatively freely.

Still, an older motor may have bearings with dried grease. If the bearings are not rusted inside, you can probably work new grease into them. and improve them greatly. I sometimes gently pry a bearing seal off of one side, work some bearing grease into them, undo any damage to the bearing seal, and tap it back into place. It is not a recommended procedure, but I figure it is suitable for a motor I use only occasionally in my workshop.

The bearings may also be bronze sleeve bearings. At the worst, you may need to go to a bearing shop and buy a match for a badly stuck ball bearing, but those are not cheap. Hopefully, your motor will run like new again with no or very little money spent.

Step 2: Add Power for a Few Seconds

Picture of Add Power for a Few Seconds

What happens when you apply power to the motor? Hopefully, there are no sparks or shocks from the motor frame, and the circuit breaker does not immediately trip. If you have any of those things, look for frayed wires in the power cord touching another frayed wire or shorting to the iron frame of the motor.

Apply power for only a couple of seconds. Coil windings inside the motor quickly heat up on a motor that does not run and the coils can be destroyed. Then the motor needs to be rewound to work again. Chances are the motor made a growling noise when you added power. It is also probable that the starting windings are not working properly, but there could be more than one reason for that.

The graphic shows the circuit diagram for this type of motor. The start winding portion is energized for only a couple of seconds. Then the centrifugal switch locks out the components of the starting winding circuit. In the next steps tests will be done to eliminate probable causes.

The second photo shows the motor running while connected to an AC Ammeter. The name plate on the motor says it runs with a current draw of 7.3 Amps. The meter is set to the 15 Amp. range. The actual reading is just a little below 7 Amps. Taking such a reading while the motor is actually running confirms that all is well. This photo was made after the motor was fully functioning as it should. An earlier reading when the starting winding was not working as it should pegged the needle, which also indicated a problem.

Step 3: Check for Shorts and Opens

Picture of Check for Shorts and Opens

Unplug the motor from its power source. Access the connections between the power cord and the motor windings. Remove the junction box cover plate, if there is one. (Make some photos showing the connections so you can make them correctly again, if you need to take them apart.) If there is no junction box on the motor, remove the end of the motor where the power cord connects to the windings.

Also, bridge the two terminals of the capacitor with a screwdriver to remove any charge that could shock you. Remove the wire from one side of the capacitor to prevent spurious readings caused by current passing through a back channel.

Use an Ohmmeter. Many suggest a setting around 2000 Ohms. Connect one lead to the iron frame of the motor. Connect the other lead to each of the wires coming out of the motor, including those that connect to the capacitor. All readings should indicate open circuits (no pathway for electricity). If any of the readings indicate a pathway for electricity, double check to be certain you were getting an accurate reading. If you still find evidence of a pathway for electricity, one of the windings is shorted to the motor frame. This could indicate the motor needs to be rewound. But, first do a visual inspection to check for a simpler explanation. Once I snagged a thin enamelled wire from one of the windings when I was inserting the rotor. The wire got a scrape that left it bare in one spot. Then it was pushed close to the iron frame of the motor where it shorted and showed a leak pathway. I was able to coat the wire with an insulating liquid and push it out of the way.

You have checked for shorts. Now check for opens. Follow the wires as best you can. The starting windings use a thinner wire than the running windings. Use the Ohmmeter to check for breaks in both windings. The resistance on each winding will be relatively low, but the starting winding will show a little higher resistance. If one of the windings shows an open circuit, look closely at where the wires attach to a terminal or to a heavier wire. Such junctions are the most common places for an open junction to happen. (I once repaired a "dead" Dremel tool. There was no indication of an open circuit in any of the armature coils. But, the field coil showed an open circuit between the two terminal pins. I looked closely and saw a break where the coil wire attached to one of the terminal pins. I scraped enamel from the wire as best I could and made a solder bridge to the terminal pin. It was not a perfect solder joint, but the Dremel worked again.) If you are not able to find the break in the coil circuit and repair it, the motor will need to be rewound.

Check with an Ohmmeter to be certain the high temperature protection reset provides and electrical path through it and that it is not broken so as to open the circuit and keep the motor from running.

Step 4: The Centrifugal Switch

Picture of The Centrifugal Switch

Capacitor start electric motors use a starting coil and a capacitor to create an advancing magnetic field in the stator (outer frame of the motor with its coils). This advancing magnetic field gives the rotor something to chase, causing the rotor to spin. (For example, put a bar magnet on top of a glass table. Bring another bar magnet up to it from under the table. Move the magnet under the table. The magnet above the table chases the magnet under the table in a crude form of an electric motor. The advancing magnetic field in the stator replaces the movement of your hand under the table.) That starting coil will be destroyed if it remains powered up in the circuit more than a very few seconds. Most motors use a centrifugal switch to disconnect the starting winding from the circuit as soon as the motor shaft builds most of its speed.

See the first graphic. It is really not possible to make a photo of the centrifugal switch in all of its parts as it is in place inside the motor, so I made a side view drawing that shows the relationship of the parts. See the text boxes.The centrifugal switch normally presents a closed circuit, if it is working properly. In an older motor fully assembled the switch's contacts may have become pitted and burned, or its parts may be worn so that there is not enough pressure to close the contacts when the motor is not running or is first starting up. Look closely at your motor and find the wires that lead to the stationary switch contacts. (One may go to the capacitor and one may be on a post in the junction box.) Connect an Ohmmeter to the contact points wires. Is there an indication of an electrical path through the switch contacts? If not, open the motor and try dragging some very fine sandpaper through the contact points to clean and polish both.

If the switch is worn, the plastic spool on the motor shaft may not be exerting enough pressure on the plate that holds the contacts for them to close fully. See the second photo. I tested my switch contacts with the motor fully assembled. I inserted a screwdriver through an opening on the front of the motor and gently applied a little pressure toward the end of the shaft (away from the motor) to close the contacts while connected to an Ohmmeter.

Be sure the rotor is properly centered end-to-end in the motor. Thrust washers may be used to move it a little, if there is space for the washers.) I made a different washer from 16 gauge steel sheet to fit on the end of the spool. The contacts on my motor now close and the motor runs. But, I also want to weld tabs to it that will fold around the end of the spool so I am certain the washer retracts when the centrifugal weights pull the spool away from the stationary contacts. I do not want that washer to float into the contacts and inadvertently press them closed while the motor is running. That could overheat and destroy the starting windings. (I looked again at my book [See step 6.]. Another option is to put a spacer under the stationary part of the centrifugal switch to bring it nearer to the spool.)

It may be possible to buy a new stationary portion of a centrifugal switch, although they are not all the same. I have not seen any listed anywhere. It is also possible to buy an electronic switch to replace the centrifugal switch. An electronic switch does not respond to the speed of the motor shaft like a centrifugal switch does, but has a timed disconnect. It allows the starting windings to be engaged for 7.4 seconds and then breaks the circuit. Electronic switches cost a bit more than $40.

Step 5: The Capacitor

Picture of The Capacitor

It is not uncommon for an electrolytic capacitor to dry out and fail in audio equipment after 20 years or less. But, replacing a start capacitor without first checking for shorted or open windings, an open reset, and a faulty centrifugal switch will not make your motor run, if the capacitor is not really your problem.

Many motors have a domed cover on the outside of the motor, and the capacitor is under it. Motor capacitors are usually a cylinder with terminals on top. But, some capacitors in older motors may also be flat, like a short stack of 4 x 6 index cards. These may be located in the base of the motor so that outward appearances make it seem the motor has no capacitor.

A capacitor may bulge or leak when it is failing. It may even split open. But, it may also look perfectly normal. There are various test procedures for capacitors, but those tests are not foolproof. A capacitor can pass several tests and still fail under a load.

If you have not done so already, use a screwdriver to short any residual charge in your motor's capacitor. Do this a couple of times, just to be safe.

If your capacitor definitely needs to be replaced, copy the voltage and capacitance numbers hopefully still legible on it. You can always use a replacement capacitor rated for a higher voltage than your motor's original capacitor, but the capacitance figures should match as closely as possible. So, at 230 volt AC capacitor can replace a 125 volt AC capacitor. The capacitance will give a range, like 220 microfarad to 260 microfarad. A capacitor rated 210 microfarad to 250 microfarad should be close enough to work well. (If you see ratings in millifarads, 1 millifarad equals 1000 microfarad.)

Here are some ways to test your capacitor. Choose those that fit what you have available.

Procedure A--With at least one wire removed from the capacitor and no power to the motor circuit, attach an Ohmmeter to both terminals of the capacitor. An analog meter is preferred, but not mandatory. The reading should rise to a high number and drop suddenly to zero or an open circuit. If there is a steady reading of some value, the capacitor is shorted. If the reading does not rise initially, something inside the capacitor is broken and there is an open circuit.

Procedure B--Remove both wires from the capacitor. Connect it to lamp cord and in series with an incandescent light bulb about 60 Watts in size. Connect it to a wall outlet. The bulb should light, although may be dimmer than usual.

Procedure C--You can get a meter that reads the capacitance value of a capacitor here for less than $20 plus shipping. The tests above give you an idea about whether a capacitor is working, but give you no hint about the actual capacitance of the capacitor. (A dried out electrolytic capacitor may appear good, but its capacitance is too low to start the motor.) A meter changes that. Search Instructables for capacitance meter circuits. At least one uses an Arduino module. About 25 years ago I had an electronics magazine with a home built circuit for a capacitance meter based on a 555 IC. (Here is a similar device you can make.) I now have a digital multimeter with capacitance reading. Some capacitance meters use a high frequency signal generator that is part of the meter. These can be used "in circuit" and give an accurate reading without feedback through other parts of the circuit.

Capacitors can give good readings on a meter and still be weak or failed. An ESR meter measures internal resistance that effects actual performance.

Procedure C'--The book mentioned in the next step provides another test. It involves measuring the current flow (amperage) used by the motor when it is powered up. A mathematical formula tells how many microfarads your capacitor yields, given the parameters of the test. It is helpful because it is a test under load.

Procedure D--It is not always feasible to buy several pieces of test equipment you may not use more than once or twice. If all else (shorts and opens, centrifugal switch, reset, etc.) checks out in your motor and the capacitor gives indications it should be good, but the motor still does not run, a new capacitor is $10 to $20 shipped to your door. At the worst, you will be out a relatively small amount of money, and it may be your capacitor has a flaw that does not show itself in the tests you are able to conduct. At the best, the motor may run.

When finished, restore the connections to the capacitor, either the old one or a new one.

Step 6: Personal

Picture of Personal

I looked at price and content descriptions before deciding to buy this book. (I do not benefit in any way if you buy the book, nor do any of my friends or relatives.) It has been very helpful. Where something lacked enough detail for me I went on-line and looked for additional material or for videos at YouTube. The book is now drenched in ink from my underlinings and marginal notes. I bought the book because some people I know somehow think I know enough to help them with their electric motor problems.

I have the 61 year old 1/2 HP Craftsman single phase capacitor start motor shown in many of the photos. (There is a 10 56 [October 1956] stamp on the motor plate.) It worked when I bought it at a used tool sale about two years ago, but the ball bearings sounded rough when the shaft was turned by hand. I opened the motor and packed the bearings with new grease. I smoothed out the seals as best I could and put them back. The motor had lots of fine sawdust packed inside. I cleaned that out. The motor shaft spun freely and smoothly when turned by hand with no power.

When I assembled the motor and put power to it, the shaft turned about 1/8 of a turn, froze, and growled. I checked for shorts and opens, but the coils are fine. I am always suspicious of older capacitors, and this one is 61 years old. I did several tests of the capacitor. It passed every one of them. I was still absolutely certain the capacitor is faulty.

I slept on the problem. I realized I made an assumption the centrifugal switch is working. I had oiled the weights so they move freely. I cleaned so the spool slides freely. When I connected an Ohmmeter to the wires that go to both sides of the stationary part of the centrifugal switch, the contact points did not provide an electrical pathway, even though I had cleaned and polished them with fine sandpaper. I inserted a screwdriver at an angle from the front of the fully assembled motor. I was able to nudge the contact plate a little with the screwdriver. Suddenly my Ohmmeter indicated a good path for electricity. I had seen a couple of wear spots on the contact plate where the spool rubs on it. I made a washer to act as a spacer between the contact plate and the spool. Now my motor purrs like a contented kitten.

After 61 years the rubber covered cord has several cracks. I bought new cord. The old cord was two wire. I bought three wire and will connect the ground wire to the motor frame to bring it up to present day standards..

I have had quite a bit of experience with household wiring over most of my life, but electric motors were still a mystery beyond a little very basic understanding. The book I bought has filled in the gaps. I now realize some logical basic testing and thoughtful deduction will help me to solve the basic motor problems I can expect to see.

Comments

jaxboy (author)2017-10-18

Excellent 'ible! I can appreciate the difficulty of trying to explain something without being able to physically point to something and say, "See this thing here? Well, do this and that." You did a very good job of verbally "pointing" to this and that, and explained everything so well that I didn't have to go back and read anything a second time to get your meaning. I wrote a few technical manuals for the Air Force, and looking at this 'ible, you would have been a natural to have done the same.

This is a good 'ible for AC motors, and here is a good help for DC motors. The bearings are the same as in AC motors, but the electrical power is applied differently. DC motors use a pair of brushes to transfer power to commutators encircling the rotor. The commutators supply power to windings on the rotor. Many times the brushes, which are almost always made of carbon, will build up a thick layer of carbon on the commutators. The easy fix to put these motors back into service is to remove the carbon build-up. Many times the motor has an access port to allow you to insert a tool onto the commutator. An ideal one is an ordinary pencil eraser. Simply scrub the copper commutator until they are shiny again. A non metallic pointed tool to gently run between the commutators completes the job.

Phil B (author)jaxboy2017-10-18

Thanks you for your comments. I am glad my explanation was clear. That means a lot coming from someone whose job it was to write technical manuals for the USAF. I spent my work life explaining biblical material for ordinary people who do not have the advantage of technical tools and terminology that were part of my training to become a pastor. Early I heard a saying I liked and tried to follow: "If you cannot write your idea on the back of my business card, you have not thought enough about it yet."
We recently moved our residence and are now very near to extended family who use tools powered with electric motors. Recently a 1 HP AC motor with a commutator and brushes quit. It had been rewound within the past year. I could find no flaws in the armature windings, but did find loose copper BBs from melted stator coils. I had hoped to find something simple I could easily repair myself.
When I decided to write this Instructsble, I chose to limit myself to one type of motor very common in residential situations.

Willys36 (author)2017-10-16

I got a 3000rpm, 3hp motor from a friend. Was his pool pump motor and had frozen up. I took it apart. replaced the frozen ball bearing and now have a fantastic polishing wheel motor that handles 10 diameter buffs without raising a sweat. I have salvaged many fractional hp induction motors with a capacitor replacement.

Anil Majmudar (author)Willys362017-10-17

I hope you added a cover over part of the buff. At 10 inches and 3000 rpm you have a lot of centrifugal force. A protective cover will be good.

Willys36 (author)Anil Majmudar2017-10-17

Yep. a steel cover and a connection to my shop vacuum system.

Phil B (author)Willys362017-10-16

Congratulations to you. I hope your friend is able to appreciate what you did without becoming jealous.

Willys36 (author)Phil B2017-10-17

No problem. He is a non-gearhead tot he max. It never crossed his mind to salvage the motor and he had no use for it anyway!

Willys36 (author)2017-10-17

No problem. He is a non-gearhead to the max. Never crossed his mind to salvage the motor and he had no use for it anyway!

deluges (author)2017-10-13

Interestingly, this capacitor fix is not at all limited to a motor.

My uncle has found that his defective fridge, microwave, toaster, bread machine AND dish washer all stopped working because of capacitor failures.

With simply a screwdriver set, multimeter and soldering apparatus he fixed all of them in no time.

Now it's the first thing I'll look at when an electric appliance fails.

Phil B (author)deluges2017-10-13

Capacitors have a limited life and do fail. Back in the days before electronic ignition a car needed new points and condenser (capacitor) every 12,000 miles or so. It did occasionally happen that a new condenser out of the box was defective. It was a difficult thing to diagnose because everyone just knew a new condenser had to be good.

KeithH125 (author)Phil B2017-10-15

Absolutely. Had a 65 ford truck and a fod 9n tractor.
Most common problem and hardest on tractor, convert to 12 volt didn't help the problem .
Condenser 90% of every issue.

Phil B (author)KeithH1252017-10-16

Our church had quite a bit of area to keep mowed. We bought a 9N tractor and a bushhog, but, it was still a 6 volt system. Thank you for your comment.

GoldinB (author)2017-10-15

Hands-on knowledge coupled with information from books is always very valuable. Thank you for this excellent article.

Phil B (author)GoldinB2017-10-16

Thank you for looking. It is also a good feeling successfully to reason out what you do not know from what you do know.

mach1950 (author)2017-10-16

This is a very well presented article sir. I am a 67 y/o electrican and everything you've said is correct, and is the best way to go about it. Although I reckon you are well aware of the dangers, I sincerely hope you are always careful not to expose yourself to live connections. 115Vac is more than enough to hurt you.

Phil B (author)mach19502017-10-16

Thank you. Very early I learned to use those hand held neon testers. Now I usually reach for a meter first.

bobbg53 (author)mach19502017-10-16

So no cheacking live wires with your toung? Im joking but i have seen someone do that with a car amp, that amp put out about 65volts ac the guy got a really nasty burnt taste in his mouth, and a big black toung to prove it worked. Always use a test meter even with a 9 volt battery.

yopauly (author)2017-10-16

Thanks, Phil! I took a 50 year old Speedaire beltdrive compressor and motor and melded it to a 33 gallon vertical tank. The oiless compressor was just too loud! In the process,the motor fell off the tank and hit the concrete floor. Empty it starts but won't start on the refill cycle. With your instructional I'll run through all the diagnostics and I'll find the problem. Thanks again. Love and peace.

Phil B (author)yopauly2017-10-16

Thank you. Let us know what you find. God's peace.

DodgeD (author)2017-10-15

A Megger meter (a trade name) is a special type of ohmmeter. It does not cause any damage, ( but can ) making it a good option when someone does not want to put holes in walls to test electrical insulation for any problems or issues. The testing device only goes between 500 and 1,000 volts, which is relatively low some units go as high as 2500 to 5000 volts and must be used with good judgment on delicate windings and circuits but because of the voltages involved electrical safety protocol is a must. Due to the low voltage, some punctures in insulation go undetected. It generally provides information about the leakage current and whether insulation areas have excess dirt or moisture as well as the amount of moisture, deterioration and winding faults.A regular ohm meter only induces a small amount of voltage through the windings and insulation so is not near as accurate, it may show everything is good but the Megger will really give you the true diagnostic what the state of the windings and insulation are. Their use is not just limited to electrical motors. Meggers can be had on Amazon and eBay at a very reasonable cost to the average consumer for home use. Just check YouTube vids for the best reviews. This diagnostic tool is great for anyone's tool crib.

JacobD89 (author)DodgeD2017-10-15

I'm glad you mentioned Meggers. There are electricians who don't know how to use them properly.

Phil B (author)DodgeD2017-10-15

Thank you for the information.

gadjetramjet (author)2017-10-15

Excellent article, Well done! I'm constantly fixin' things this will prove useful. A short footnote, I have a small lathe, craftsmen, same year as your motor, same color etc. The motor has been replaced years ago, it used to look just like that one, but with a single spindle. I've found, like you, follow the flow of electricity...

Phil B (author)gadjetramjet2017-10-15

Thank you for your comment. This motor was purchased at a used tool sale with a small metal lathe also sold by Craftsman, but the motor had obviously been used with a woodworking tool. It was full of very fine sawdust. I bought it for a member of extended family, but he never used it. Now it is back with me at his request, as is the lathe.

gadjetramjet (author)2017-10-15

sorry ... hitting the wrong button not good! ... Follow the flow of electricity... and all shall be revealed!

Timbergetter (author)2017-10-15

Thank you for your excellent introduction to motor servicing. An important fact that you touch on is that the current draw during motor starting can be 4 or even 6 times the rated current for a given motor. So if your shed is at the end of a long length of lightweight cabling then you may not have enough grunt to reliably start your motor even though, once started, it can happily run all day. This situation becomes more critical with larger motors of say 3 HP.

Phil B (author)Timbergetter2017-10-15

Thank you for your comment. It is very true that even after my motor was working as it should, the current draw on the Ammeter went much higher than the normal load until the motor reached its run speed. Because my father was an electrician I well remember times when someone on a farm needed electrical service for a building some distsnce from the main service panel. There was always a voltage drop and a larger size cable was required to supply what was needed at the back end. Every instructional booklet I have seen for a new cord powered tool has a chart on wire size per feet of run from the main service panel. Thank you for looking.

BeachsideHank (author)2017-10-15

We now find 2 pole motors becoming more dominant than back in the day when 4 poles were the norm, I suspect that the more economical 2 pole is preferred because of the money saved by manufacturers, as usual. ☺

Phil B (author)BeachsideHank2017-10-15

Thank you for the information.

bradbakalyar (author)2017-10-15

very well written and educational Good Job

Phil B (author)bradbakalyar2017-10-15

Thank you for looking.

jim.kohler.927 (author)2017-10-15

We often had electric polishing machines sent to us for repairs and the first test we did was to check the continuity of the live and neutral wires from plug to motor. Most times this was the problem sorted.

Phil B (author)jim.kohler.9272017-10-15

That is certainly wise with a corded machine, in which case the cord may have failed due to all manner of abuse. I strongly considered a direct statement about making certain there is power reaching the motor. I am also assuming someone who will check for shorts and opens also knows to check for reliable power reaching the motor. I hoped my mention of the probability the motor growls implies it is certain power is reaching the motor.

Kuberkoos (author)2017-10-15

My first step in testing a single phase motor, is to apply power and spin the shaft by hand. Be it cap. start or cap start&run, it would start if the switch or the cap is o/o/o

Phil B (author)Kuberkoos2017-10-15

I do not usually use what are probably urban dictionary symbols and slang. I am not completely sure what o/o/o means other than it implies something either does or does not function properly.

I have seen suggestions by some that they also try spinning the rotor by hand to see if the motor will begin to run on its own. I like to start with the most basic things and check them, moving to the more complex things. I probably approach all problem solving that way.

JohnG26 (author)2017-10-15

well done I have revived many a motor myself,they don't make them this strong anymore

Phil B (author)JohnG262017-10-15

Thank you for the affirmation. I am making the assumption capacitor start and capacitor run motors are the bulk of what I will encounter. At 71 years of age now and not really in the business, that is probably true.

fjgomez (author)2017-10-15

Thank you Sir excellent

Phil B (author)fjgomez2017-10-15

Thank you for looking.

ajayt7 (author)2017-10-15

Very informative, thanks

Phil B (author)ajayt72017-10-15

Thank you for looking.

rayp1511 (author)2017-10-14

Interesting and useful info. Thanks for posting it.

Phil B (author)rayp15112017-10-14

Thank you. Some self-interest is involved so that the next time I have a problem this Instructsble serves as notes I can review. If you have any long term interest in electric motors, I really recommend getting the book I mentioned.

USMC-USAF-USN (author)2017-10-12

Thanks for a detailed process for trying to restore an old motor to usefulness. Excellent, as usual with your work. I really like your RAS series; I am starting to get mine set up again after a big move.

However, I saw one problem with checking capacitors - getting the unit prefixes turned around. It takes 1000 microfarads to make 1 millifarad.

Phil B (author)USMC-USAF-USN2017-10-13

Thank you for finding my mistake. I have corrected it.

A radial arm saw can be very versatile, but I often saw people using them as a table in the garage for storing garden chemicals and paint cans, or using them as an oversize chop saw. We also moved recently and mine is still in pieces on the floor. But, I need metal things more than wood things right now. Thank you for your comment.

I wish I had thought of all of the things I post. I borrow a lot, but also try to credit sources.

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