Hi all,
I have an old United brass HO 2-8-0 that I’m trying to get running. I tested it on my test track, and it is completely unresponsive. No buzz, lights, or anything. I think this loco has the original motor in it.
I tested my track with a voltage tester, so no problems there.
I don‘t have much experience with troubleshooting locomotives, so what do I need to check to see if I can get this thing running?
Thanks
Take the shell off and look for anything not connected (e.g. a wire that snapped off the motor). Check that the brushes have continuity to each rail (or at least pickups on each side). It probably picks up one rail through the drivers, and the other rail through the tender -- so make sure that the loco / tender connection is good too.
-Dan
Builder of Bowser steam! Railimages Site
Hi,
Here is a .pdf showing some of the things to look for in older brass that you might find useful:
http://schutzer.net/Brass_Clinics/RebuildingBrass2008a.pdf
I had one case where the rubber sleeve between the motor and gearbox had hardened so badly that the motor shaft could not turn at all.
Do you have a power supply or multimeter you can use to see if there is any current draw at all? This will tell you if you have an open circuit or a short.
If it is an open frame motor check the brushes, armature and brush springs for good condition.
Good luck, Ed
Most important... and you did not say...
.
Is the tender on the track and attached to the locomotive?
On United brass locomotives the tender is the other half of the circuit, and it must be attached to the locomotive for it to function.
Let us know if it is that simple, if not, I can give you a few tests to do.
-Kevin
Living the dream.
SeeYou190Is the tender on the track and attached to the locomotive? On United brass locomotives the tender is the other half of the circuit, and it must be attached to the locomotive for it to function.
Kevin,
I think that would be true for just about any of older brass steamers.
Tom
https://tstage9.wixsite.com/nyc-modeling
Time...It marches on...without ever turning around to see if anyone is even keeping in step.
Yes the tender was attached. I will be extra sure to make sure of a good tender connection next time I test it. I got the shell off and the motor is very dirty. I am going to try and clean it first.
Also I think a wire is missing. there is one going from the tender connection to the motor. That is the only wire I have found. There is a bit of solder where it looks like another wire came in, but I have no idea where it went on the other end (a connection with the driver pickups I assume).
it looks like a pretty simple setup, (especially compared to today’s locos), so even an electrical chump like me should be able to get it running.
Thanks y‘all for the help.
SeeYou190 Let us know if it is that simple, if not, I can give you a few tests to do. . -Kevin .
Thanks! That would be great.
Usually the other brush of the motor would be grounded to the motor's frame, and from there through the loco frame, which is energized because the wheels on one side are not insulated and thus conduct power from the rails to the bearings to the frame. Perhaps this loco was different, or it was previously modified to isolate the brush - something you'd need to do to install DCC.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Union Pacific 428Also I think a wire is missing. there is one going from the tender connection to the motor. That is the only wire I have found.
There should only be one wire. It runs from the insulated drawbar connection to the motor brush. The entire locmotive is the rest of the circuit, so it does not need any additional wires. On my United locomotive the screw that holds the motor to the frame completes the circuit.
The next test should be to take voltage directly to the insulated lead and the driver frame and see if the motor runs. If it does, the problem is in the electrical pick up.
I do this with a regulated voltage supply and Fluke test leads, but it can be done with any ordinary power pack.
Ok so when I took the shell off a screw did come out of the area under the motor. I didn’t think too much of it at the time, but I’m thinking that could be the culprit. I have been trying to get it back into the screw hole in the motor frame just in front of the last driver, which is where I think it came from. This is proving to be an extremely difficult task. I am going to see if that gets it running, then do the test for electrical pickup if not. Thanks again everyone for your assistance. I’ll keep you all posted.
UPDATE: So I think getting the screw back into place will be impossible. Just not enough room to get it upright so it will go into its hole. I'm not even sure how it was able to "escape" in the first place! What should I do? Try and get a smaller screw or try a small length of wire to finish the circuit or what?
if it came out, it should be able to go back in
if you're that desperate, put the screw on the screwdriver and drip some wax on it or use glue from a glue stick to hold it on screw driver so that you can get it into place.
greg - Philadelphia & Reading / Reading
Union Pacific 428What should I do?
https://www.micromark.com/Micro-Screw-Starter-for-Slotted-Screws
There's another type with three or five little wire fingers, too.
Either way, a good tool to have for coupler screws, and such. There's a different tool for phillips.
You might have to remove the "cover plate" that holds the drivers in place in order to access the motor mount screw. BE VERY careful if you do, don't bump or tip the locomotive. There are probably, or at least there should be, super-tiny springs between each driver's bearing box and the frame. Do you have a foam cradle to set the locomotive in?
Consider replacing the open frame motor with a stronger, smoother, lower current draw can motor.
IMG_6621_fix (2016_08_17 08_08_12 UTC) by Edmund, on Flickr
There's an Ebay seller that specializes in various can motors at a reasonable price:
https://www.ebay.com/str/Sweetwater-Locomotive-Repair?_trksid=p2047675.l2563
Or look at NWSL for a complete upgrade of the drive. This would give you the best, trouble-free operation for years to come.
https://shop.osorail.com/category.sc?categoryId=14
Many older, open frame motors have developed weakened magnets over time. Some fellows replace the magnet with stronger rare-earth magnets.
Good Luck, Ed
gmpullman Consider replacing the open frame motor with a stronger, smoother, lower current draw can motor.
So would this be a better option? I am planning on installing DCC at some point, so maybe it would be best to go ahead and install a can motor at the same time?
Union Pacific 428So would this be a better option?
Yes, I believe it would. You really don't have to get too fancy with mounting, in my opinion. You can see mine is stuck to the frame with a inch or so of double stick foam tape and a few wraps of strong Kapton tape.
The foam and tape also isolate the motor from the frame so less vibration and noise are transmitted. All the can motors I've encountered so far have isolated brushes, although that isn't a real problem for open motors in most cases either.
IMG_6626 by Edmund, on Flickr
Some guys will use silicone RTV. A metal bracket would be ideal, of course, but I don't see the need as long as a good clean surface is prepared.
Go back to my first reply and click on the link for the summary of improving brass steam. There are some good pointers there. MR has had a few articles over the years, some dealing with DCC conversions, too.
With the motor removed, check for slop in the gear box, too. Sometimes too much lateral movement in the worm can be taken up with thrust washers. Clean the grease out and freshen it up, too.
Have fun, Ed
UPDATE: I have decided to go ahead and replace the motor. I think I’ll wait and see how the gearbox runs before I try replacing it. Thanks everyone for your help.
Union Pacific 428I have decided to go ahead and replace the motor.
Most replacement motors have two leads, so you will need to run a wire from the locomotive frame to one of them. Replacement motors generally do not "ground" through the motor frame.
If the locomotive runs in the wrong direction, just swap the wires.
SeeYou190 Union Pacific 428 I have decided to go ahead and replace the motor. . Most replacement motors have two leads, so you will need to run a wire from the locomotive frame to one of them. Replacement motors generally do not "ground" through the motor frame. . If the locomotive runs in the wrong direction, just swap the wires. . -Kevin .
Union Pacific 428 I have decided to go ahead and replace the motor.
Ah ok! Thanks for the advice, that’s good to know.
You can also use silicone to install your new motor. Good luck!
Simon
snjroy You can also use silicone to install your new motor. Good luck! Simon
Thanks! Will using silicone insulate the motor from the frame for DCC installation?
Union Pacific 428Will using silicone insulate the motor from the frame for DCC installation?
The outer case of the can motor is already isolated from the two connection points.
You can double check with an ohmmeter to be sure but any can motor that I have dealt with are electrically isolated from the input leads.
I have also never encountered a replacement "can" motor where the motor case had continuinty with one of the motor leads.
Good to know about the can motors. I have cleaned out the old grease and added new to the gearbox. When the new motor comes in I will keep y'all posted on how installation goes...I'll probably have more questions. Thanks again everyone.
Hi there. You will need to connect a wire from your frame to your motor (or decoder). That is probably the most tedious part of the operation... I drill a hole (by hand) somewhere on the frame near the cab, tap it, and install a 2-56 screw that I can connect a wire to. It is a lot easier to do than to solder something on... But others may prefer to solder a wire.
Thanks Simon for the tip. Thant's good to know.
The motor arrived yesterday, so I will be installing it soon. 2 more questions before I start though.
1) Does the wire to the loco frame need to be attached to a specific side or can it be connected anywhere?
2) The driveshaft on the motor is too long. Can I shorten it without screwing up the motor somehow? If so what is the best way to do it? Unfortunately I don't have a dremel. Would rail nippers work? Hacksaw?
Thanks again everyone for all of your help.
Hi. Anywhere on the frame. I drill a hole near the cab so it won't touch anything. A dremel with a cut-off disk is best to cut the shaft... I assume there is no room for a flywheel? I guess that a good pair of pliers could work. Maybe Santa can get you a dremel. It it extremely handy to have for these things.
It does have room for a flywheel. Should I put one on? There is also a very short rear shaft that might accommodate a small flywheel.
flywheel is more important when running on DC than DCC. I read many discussions if a flywheel has an impact when running on DCC, I am not sure if people will ever agree on this. I remove all of them on my locomotives when converting to DCC, but it is just my choice.
If you will install flywheel, be careful to install it absolutely centric, because if flywheel is out of balance, it will cause vibrations when motor will run at higher speeds. When and if you install it, you can test if it is installed propely by holding motor in your hand and applyin power on motor leads. If you feel no vibrations (like when flywheel was not installed), it is ok. If you feel vibrations, flywheel was not properly installed. If you buy flywheel from NWSL, it comes with short guidance how to install it using vise and rotating flywheel gradually so it slides on the shaft properly.
When you cut shaft if it is too long with cutting disc, it would be wise to cover the rest of the motor with masking tape, in case motor has any opening. For example, holes for mounting screws, usually on the side where shaft is. If any metal particle enters motor thru these holes, it can damage motor or at least cause problems, if it later comes thru motor to commutator/brushes. It is just a precaution, very probably nothing would happen even without masking tape, but it is easy to apply it, therefore I would do it (I do it when I cut shafts on motors which have any kind of hole on them).
Hrvoje
I made a photo of above mentioned NWSL instructions, how to install flywheel correctly:
Yes, some advocate that flywheels can confuse the BEMF abilities of a decoder. I prefer to disable BEMF altogether. Unless you are using a keep alive decoder, a flywheel helps prevent unwanted interruptions due to loss of electrical contact (e.g. over switches). I find that locos with flywheels run better in both dc and dcc...