Can motors life span

I have not, as yet, managed to wear out any of the can motors in my O gauge trains.

I do know this from my experience with electric powered model airplanes:  Brushless motors, unless severely abused, do not wear out.  And in case you use one long enough to tire out the bearings they are easily replaced.

I look forward to the day when brushless motors and wireless RC are a part of the O gauge hobby.  Until that happens I'm stickin' with conventional.

Pete

Pete,

Assuming that all motors in MTH engines are brushless, do these have bearings that can be replaced? I have a couple older engines I acquired plus a new one that exhibit a whirring/chatter noise that I know is not the wheels or gear drive. I have always suspected motor bearings. Do you think that's what I'm hearing?

Thanks, S

I am pretty sure most of the motors used in our trains have brushes. This includes all of the Mabuchis and most of the Pittmans, at least the ones used in Lionel engines. Not familiar with the big motors used by MTH. Most have oilite sintered bearings as well. A drop of oil on the bearings will tell you you if what you are hearing is worn bearings. They should quiet down for at least for a few minutes.

Pete

Best to never assume.  I figure all modern train motors are brushed, can type.  Brushless motors require a unique speed controller not seen, as yet, in modern toy trains.  I have no MTH stuff, but it may be possible to lubricate, if not replace, the bearings.  Sorry I can't offer more help.

Pete

Brushless motors would be great, but I doubt they're coming anytime soon.

 Before Lionel developed the odyssey system, they developed the Odyssey Motor. The Odyssey Motor was to be the replacement for the Universal "Pullmor" motor. There are a few prototypes around. The Odyssey motor was similar to a squirrelcage asynchronous induction motor. The rotor RPMs would be controlled by phase. Not diving too much into history, but Lionel developed the motor and speed control and then dropped it. 

So we have seen brushless motors and speed control in our trains; just did not make it past the prototype stage at Lionel. 

Found a picture

 In the R/C world, brushless motors are extremely popular. Electronic speed controllers and the motors themselves are becoming quite reasonable in price. No doubt that these could easily be adapted to O gauge trains.

Asynchronous induction motors are vastly superior to permanent magnet can motors. After all, asynchronous motors are the traction motors that the prototype's use. 

Thanks Pete. Will look at the motors to see if there's a spot to add oil. Would be great if there was an exploded view or diagram to look at. Otherwise maybe I'll try to take one apart over the holiday.

FWIW, Jon Z. mentioned the AC cruise control once, he said they could never get the low speed performance to a level they considered satisfactory, which is why it never saw the light of day.

I agree that brushless motors would be great, I developed avionics for many years, and we were a large user of brushless motors, they have an impressive MTBF since they were all ball bearing motors.

They seem indestructible.  I use a lot of bigger can motors in various projects and have learned that a good way to get them for projects is to buy an otherwise trashed loco with can motors at a swap meet.  Sometimes I get two good ones, worth $23 each new, for only $15.  I have yet to ever encounter a loco that hascan motors where the one or two inside it don't work perfectly once removed.  I'm sure they do wear out, and that they can be destroyed by abuse, but I haven't seen any evidence of that so far.  

I seem to recall reading somewhere that the brush life on the type of can motors that are in our O gauge trains on average last over 10,000 hours.  That's certainly longer than the average brush life on the open-frame motors, and the can motors are pretty inexpensive when it comes to being a replacement part.  While repairing the older motors is certainly cheaper than a new can motor, I think the greater frequency of open-frame motor maintenance puts it more into the diminishing returns category just from that standpoint over can motors, but other's mileage may vary of course.

The bearings are on either end of the housing at the base of the motor shaft, A drop or two of oil on each end should do the trick. If this is a steamer, you'll probably have to hold the loco vertically in each direction and spin the flywheel to work in the oil.

On diesels the motor(s) need to be removed from the truck to get oil on the lower shaft bushing.

Oil should take care of squealing bearings as long as you haven't run them countlees hours with the noise.

IMO,as tedious as it would be to replace the bearings if it were possible, it would be far less work just to replace the entire motor. Then you have a new motor and new bearings.

Thanks Rick!

Just the info I was looking for. I have an MTH diesel from my "what was I thinking" collection that I will experiment on. If the lube fix works then I'll look into motor replacement as you suggest.

S

Just use a good quality lube. I use Labelle 102, its a "heavier" light oil that stays where its put.

Squealing smoke unit fan motors is a fairly common problem as well, oil typically resolves it.

We operate MTH, Atlas, and Weaver Diesels at the O Scale portion of the San Diego Model Railroad Museum.  I am currently the mechanic - kinda my donation.

We have a couple of motors that wore out the bottom bearing, and all I did was re-bush it with some porous bronze.  Most of the Diesels have had multiple axle gear changes, and several have had worm changes.  Two have worn out the axle bearings and axles.

I have never, in 20 years of doing this, replaced a motor because the motor itself was bad.  Before I learned how to replace the worm, we did replace two motors.  The MTH mechanisms have maybe triple the longevity of the others, even though the gears appear to be the same.  I believe it is due to how the worm shaft is supported, and the design of the gearbox itself.

But to answer your initial question, Charlie Pittman told me personally that his bronze bearing motors would last 800 hours if you did not side- load them.  All of the above Diesels have bronze bearings, and all are side- loaded.  The Museum operates eight hours a day!

Actually, 800 hours doesn't seem all that long, in a place that operates them 8 hours a day, you'd go through a motor in what, three months?

I'm stunned you have never seen a genuine bad motor, because I can ship you two that are certifiably bad, one will still run if you don't mind the wisps of smoke coming out, the other one is as dead as a doornail!  Both of these are from MTH locomotives.  Don't get me started on the small Lionel starter set motors, I replace them on a regular basis, and they are indeed really bad!

bob2:  Any techniques you would like to share with us on how you change worm gear on the can motors?   We all know that this particular proceedure is critical, and can render a good motor, bad, if done poorly.  Dennis M.

I'd like to hear that as well.  I suspect he has better tools than I do for this task.

Before we put in the push buttons and timers, 800 hours is about what we were getting with the William's can motors used on Tom's Train Station's display layout in South Hills Mall, Raleigh NC. They ran continuously 8 to 10 hours a day, 6 days a week before the timers went in. I think heat build up in the motor and truck from running continuously that long contributed to the shorter life span.

Now all the tracks are on push button activated timers set for two minutes. That's not long enough for friction to build up much heat, and the locos get at least some break between runs.

I was under the impression that the better can motors, Pittman, Mabochi, etc, are equipped with ball bearings.  if so they ought to last, darn near, forever.  Not so sure about the brushes, however.

Paul Fischer

I used to work at a hobby shop in South Fla which had an outdoor LGB layout out front.  We rotated 3-4 different engines and trains but what ever was picked ran all day from 9AM to 6PM.  I replaced at least a half dozen LGB can motors in the year and a half that I worked there.  We also ran a Lionel G scale Thomas and I think I may have had to swap a motor on that maybe once.  I do remember the eyes getting stuck a few times from gunk build up though.  Those were pretty good trains though, I used to clean the track every morning, put the train out and literally just leave it, all day.

As long as can motors have brushes and bearings, they will not have infinite life.  We are just lucky that in reality, most engine's are only run a a very small amount of time compared to the designed life span of those motors.

None of the Mabuchis have ball bearings. The Pittmans used by Lionel do not have ball bearings either, at least the ones used since 1998. Not sure about the new Buehlers used in the Legacy engines.

Pete

quote:

I was under the impression that the better can motors, Pittman, Mabochi, etc, are equipped with ball bearings.  if so they ought to last, darn near, forever.  Not so sure about the brushes, however.

Maybe they are not considered can motors, I had the impression that some of the older, better made D.C. motors had renewable brushes.

The better can motors do have ball bearings, silver-graphite brushes, and rare earth magnets.  That is the way I order mine.  Costs about five bucks more per motor, at least last batch I ordered.  No mass- produced toy will add that expense, which is why all your models get solid bearings.

You do not need to believe me when I say we do not get burnt- up motors.  You can choose to believe that I am replacing motors as often as I replace axle gears, but just not willing to tell you.  On the other hand, ask the club members if they are springing for motors.  The answer will be "rarely".  I have no idea why they outlast the worms.

I use two pieces of steel, machined so they squeeze in between the worm and the motor end bell, and meet.  They support the worm, with the motor hanging beneath them in the open jaws of a heavy vise.  A bag with foam is just below the motor to catch it - no surer way to kill a motor than to drop it!

Then I apply heat with a torch to the worm - quickly, so as not to heat the motor shaft too much.  A drift pin and hammer complete the task.  The heat releases the shaft Loctite.  The new worm is installed with Loctite.  If it takes force, I am very careful to apply all force axially.  I have done this about six times - we seldom wear out the worm.

Our most common mechanism failure is the axle gear.  MTH takes about three years of operation to kill that little bronze gear.  Both Atlas and Weaver use a more complex jack shaft arrangement, making it easier to replace the shaft.  But it introduces something mechanical that causes failure about three times as often.  I prefer the MTH setup, even though the press fit is really, really tight.

We have been running MTH 2- rail for about a quarter-century.  The most common failure is the electrical pickup wipers.  These are good units.

John,

Of interest is the distinction between wearout and failure. Wearout, where bearings, brushes or other components subject to contact or electrical interaction wear down over time to the point of performance degradation but can be restored to full performance with maintenance. Failure, a sudden loss of performance after a short time due to defect or poor design and/or poor fabrication practices. In the latter case there is often little value in repair and the component must be replaced.

I have an older MTH switcher where the engine purrs along silently and the gear trains on both trucks are tight as a drum. I imagine that the motor/gear drive trains on this engine will outlast me. I also have a PS3 diesel with all kinds of slop in the drive train and motors that emit unacceptable noise. I am of the opinion that the PS3 drive trains are either poorly toleranced or fabricated and bound to fail sooner or later.

I envy the guys -- like you and Bob2 -- on the forum that are handy and comfortable with engine servicing and repair. Servicing a worn out component and restoring full performance is -- to me -- a fun part of the hobby . Repairing something that wasn't done right not so much.

Kind of a ramble-y post but I needed a break from proposal writing.

I have taken can motors apart and reassembled them.  You could actually rebuild them if you wanted to.  I don't think the brushes are the weak link.  The motors that I see bad, have had the armature overheated and the winding either shorts or opens.  So if the SD museum, doesn't over load the engine, I could see how the gears wear before the motor fails.  I will say I have seen a lot of failed motors though.  You can tell the difference in the color of the armature windings.  G

Getting them off a bad motor is not the issue.  I use 2 motor cycle tire irons that are thin enough to slip between the gear and the can.  Follow same procedure as Bob2, but I don't use heat.  I have run into a flywheel or 2 that did not want to come off.

Pressing on is where you need to be careful.  You also need good measurements on where the flywheel and gear are located on the old motor so that you press them on to the same locations on a new motor.  G

Many Pittman motors do indeed have replaceable brushes.

While we're on the subject;  many of the new cordless power tools being offered by the major suppliers, are now touted as being "brushless".   The tools are lighter and supposedly more powerful than their older designs with brushes.  I'm not sure just how these motors work, but they are variable speed and seem to be a bit quieter than the older models.

My question is: could this technology be adapted for model train motors?  After all, brushes do seem to be one of the weak points, or at least a requirement for service at time.  What with the modern electronics available now, it would seem to me that our manufacturers could come up with a really quality "brushless" motor for our expensive engines.  Could also throw in ball bearings, too.

Paul Fischer

The very few motor failures I have had on model trains are either cooked armatures or worn out bearings.  I am sure brushes wear out, but the only bad ones I have seen were due to mechanical failure, not wear.  Even the old auto generators seemed to go on forever - my ancient Ford would stop genning now and then, but washing the crud off the brush assembly would get it going immediately.

Your toy train manufacturers are looking for ways to keep prices down, not drive them up.  Ball bearings are industry standard, but not model train standard.

A good Pittman can be installed in any of your locomotives, but watch the speeds.  Some models are geared for the faster- running Chinese windshield wiper motors.