Can you fix a 9v train motor?

[ecmo47]

Two of four of my 9v train motors conked out 3 days before my first show. One motor seems to run fine by itself but when you add to a locomotive, it doesn't have enough "umph" to move. The other motor will pull a train for a few minutes then just stops. Is there a fix for either one? For starters, is it even possible to open the motor?

Edited February 17, 2015 by ecmo47

[Richfilth]

I repaired a motor that was operating similarly to yours. The problem was the thermal fuse that's fitted to these engines to protect them (a little round disc sandwiched between the motor and the pickup connectors).

I used this guide to open up the case (scroll down): http://horst-lehner....ben/9v_12v.html

Then I found the fuse, pulled it out, and gently bent the brass tabs on the motor to make a stronger connection to the pickup conductors.

With the fuse removed, it's not recommended to run these motors for too long, and avoid stalling them, but at least they'll pull again. Unfortunately I haven't found a source for replacement themal fuses.

Edited February 17, 2015 by Richfilth

[ecmo47]

Thanks for the reply. I'll give it a try. Any idea what "too long" (to run these motors) would be?

[jtlan]

Thanks for the reply. I'll give it a try. Any idea what "too long" (to run these motors) would be?

I've never heard that about the de-fused motors. I think a lot of our LUG members have taken out the fuse, and their motors run for many hours continuously at shows. I suspect the failure point of the fuse is far below that of the motor itself, so you shouldn't have anything to worry about unless you really overstressed it (say, by jamming the wheels and running it at full power).

[SavaTheAggie]

Hook up the motor to a 9v or PF battery box. The power works in both directions - you can supply the motor with power from the rails or through the "Accessory" attachment on top.

If the motor runs as expected while hooked up to battery power, then the fault lies in the brushes that pick up power from the rails (in my experience the first thing to die on a 9v motor).

If the motor performs poorly even with the battery box, then the fault lies elsewhere and is a more serious problem.

As for fixing the problem, I don't *know* how to do it, but I have seen online guides showing people pulling motors from the PF motor and inserting it into a 9v motor (with some slight customization to make it fit) or even replacing the brushes.

--Tony

[ecmo47]

Thanks for all the advice. One of the motor ran fine with no load on it so I "fixed" by building a shell around it and turing it into this rocket car! Should be a crowd pleaser as it zips around the track. I will definitely op check the other one following the above information as it will only run a few mintues before stopping.

DSC01069 by ecmo47, on Flickr

DSC01067 by ecmo47, on Flickr

Edited February 17, 2015 by ecmo47

[Lazarus]

Sounds like the bushes are gone in the motor and at some point it will die or die after about 15-20mins of running.

Ref my fix guide.

http://www.eurobricks.com/forum/index.php?showtopic=83667&hl=%2Bfixing+%2Bmotor

[ecmo47]

Thanks for the link and your excellent "how-to" videos. Very clear and concise.

[legoman666]

I made a quick how to a couple months ago for repairing worn out contacts.

http://www.eurobricks.com/forum/index.php?showtopic=102241