EUREKA, problem solved thanks to all of your great help. Lesson learned for me. Once the wheels and trucks aligned re polarity/ insulated: non-insulated problem solved.
Thanks again for the great help with this. Now the old E7 should look pretty good with the new E8---C,B&Q,, assuming I can get the Kadees ordered and properly installed!
Randy (and others) you may be on to something. I took the trucks apart again and found some copper uptakes which I totally removed. Tried it again, same problem.
Now with the trucks open I see (being an electrical nitwit) that there are insulated and non-insulated sides of the axles and they were not in sync ie aligned. I also see one side of the truck support is plastic and the other metal. Am I correct to assume the metal side of the axle should be on the metal side of the truck support?
I am getting them all aligned the same way and will be off to the basement again shortly.
THANKS.
Tarhawk
Did it have wires going from the trucks to the motor? Is there any chance they are touching? When you removed allt he drive train, did you remove the trucks? Perhaps you put one back on the wrong way, putting the insulated wheels on the wrong side, that would cause what you describe - with it getting worse when pushign down because you get better contact between the truck and the bolster.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Okay, tried it with shell off.
- Power on to tracks, another engine selected on the Zephyr
- Dummy E7 on a different track
- while sitting still seems to be no problem, however....
- if I manually move the E7, the selected engine cuts in and out and the numbers flash on the Zephyr. Almost seems to happen even if I just push down a bit on the E7 but definitely with movement of the E7.
Some updates:
- this is an old heavy metal Model Power E7
- the engine is entirely removed as are all gear wheels
- currently has no couplers, ordering appropriate Kadees
- the wheels appear aligned and stable, no lateral movement
- there is no B unit attached
I am off to the basement to try it out with the shell off; it still hums and I get message on Zephyr will let you know. If it does the problem must be somewhere in the trucks. I am reluctant to take them apart again since they are a pain to get back together but may have to.
If it's an AThearn blue box and you used #5 couplers - it IS a short between the chassis and the coupled loco. If you have just a single A unit coupled to the B dummy, and flip the B unit around - I'll bet the hum stops, because now the chasiss of each is connected to the same rail, no short.
Kadee has plastic shank versions of their couplers for such purposes, otherwise you need to dring down the mounting pad and use the #5 in its box, the box is plastic and insulates the coupler from the chassis.Most newer models with a 'hot' chassis come with plastic coupler boxes so it's an issue that is often forgotten but has always been around - it was a problem with DC as well.
Quote:
“removing most of the motive parts”
Be specific.
Get your self a digital meter and learn how use it, especially the ohms part to look for shorts or continuity of wires. If the motor is still in the loco, a check between wheels one both sides would show some low resistance, maybe 25 ohms to maybe 100 ohms indicating the motor is still connected or a low resistance somewhere in the remaning electrical connections.
A cheap but very usefull digital meter for model railroading. I have three of these meters.
http://www.harborfreight.com/7-function-digital-multimeter-90899.html
Rich
If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.
If this is an Athearn locomotive and you did not remove the motor, the humming noise could be from the square-wave AC DCC voltage getting to the motor through the bottom brush clip, which touches the frame.
If you removed the drive shafts but not the motor, the motor may actually still be receiving voltage and thus the humming noise if there's any electrical connection at all between the top motor brush and one or both trucks.
Remove the motor and the humming should stop.
WHat message did the Zephyr display?
Simon Modelling CB&Q and Wabash See my slowly evolving layout on my picturetrail site http://www.picturetrail.com/simontrains and our videos at http://www.youtube.com/user/MrCrispybake?feature=mhum
Thanks very much. Several things to consider. I have removed the gears. I will need to reopen and check for the other items mentioned above. As the week progresses will check it out and report back. The Digitrax Zephyr did not shut down, just sent a message. We shall see! Thanks again!
tarhawk When I removed it from the track the DCC engine proceeded to work fine.
When I removed it from the track the DCC engine proceeded to work fine.
My first worry is Did Your DCC System Shut Down So There Was No Power To The Rails? If the system did not shut down and kill the power, you have a bigger problem that the E-7. I may have missed read, but a dead short has to shut down all the power, or ever decoder you have is at risk of BBQing. Ask me how I know, I burned up $200.00 in decoders before I found my problem.
Now back to the E7. If you did pull the motor first thing I think of is your wheels are out of gauge. If the gauge is to narrow, left and right axles can touch and cause a dead short, I have had it happen on a few of my engines. Sometimes it just happens over time, but you all so check for a cracked center gear as well. When the gear cracks, it will not hold axles tight and the wheels will come out of gauge.
Cuda Ken
I hate Rust
I would suspect that your issue is in the trucks.
You said you removed "most of the motive parts", what did you do with the electrical power pickups? Even though you cut the wires, if you left the contacts intact on the wheel sets you may have inadvertently created a short between the two sides of the track.
And if you took the trucks apart, did you make sure that when you reassembled them you preserved the polarity of the insulated and non-insulated sides of the wheelsets? You might not think that it makes a difference, since the unit is no longer powered. But if part of the circuit goes through the sideframes, and you reversed a wheelset, you could have a short through the truck itself.
I have figured out what is wrong with my brain! On the left side nothing works right, and on the right side there is nothing left!
Metal coupler mounted to a metal frame? That is what comes to mind from the old Athearn blue box locos.
When you stripped out the running gear did you remove the worms from the gear towers? If you take them out it will roll easier.
Pete
I pray every day I break even, Cause I can really use the money!
I started with nothing and still have most of it left!
Did you remove the motor? How about the light board?
I have converted an old E7 to a dummy by basically removing most of the motive parts and have cut all the wires. Nevertheless the other day when trying to use one of my DCC engines I got a short indication and then listening carefully could hear an electric hum from the E7. When I removed it from the track the DCC engine proceeded to work fine. Is there something in the trucks that would cause this or is there an electrical ghost in the engine. Since most of electricity is a mystery to me I am going with the ghost theory for the moment! What else do I need to do to truly create a dummy from this engine that will not short circuit the track? Thanks!!