4-8-2 light mountain

[newguy]

HI everyone, I'm new to the model train world. I have collected a few locos and just received a brand new spectrum 4-8-2 light mountain. I opened it up and the first thing I noticed was that something was rattling in the tender then the front wheel assembly came off and i realized the screw was missing. I removed the cover and located the screw and got it all back together just as the diagram shows.

Afterwards, I placed it on my track that I know works, turned the dial on my digital commander and... nothing. I tested another loco - no problem. I tested it with a new athearn dc power pack - nothing. I noticed that when I pick up the front wheels of the tender the loco begins moving but the second they touch the track everything stops except the light in the cab of the loco. In case you were wondering, the loco is not dcc equipped and is not dcc - ready at least it doesn't say so on the box. There is a wire harness that connects the tender to the loco.

Questions:1.!What does the circuit board in the tender do?
                  2. Why doesn't the loco move on its own without being attached to the tender?
                  3. How do you think I can fix the problem?

[Mike]

Try taking off the front wheel set again and reverse it. It sounds like you reversed it when you replaced it. HO wheel sets have at least one side insulated from the axle. If you reverse one truck (or an individual axle/wheelset in a truck) you can cause a dead short. Let us know how it works out for you.- Mike S.

[Jim Banner]

It sounds like the front truck on the tender is backwards.  Try turning it 180 degrees.

Does the circuit board in the tender look something like this?



In particular, does it have the 8-pin socket on it?  It would likely have a dummy plug set in the top of it, obscuring the view of the pins.  If so, then this board is where you can plug in a decoder if/when you want to convert your locomotive to DCC.

See if there are TWO plugs connecting the locomotive and tender together.  I would typically expect one 2-pin and one 4-pin plug.  Then the 2-pin plug carries the power from the locomotive wheels to the circuit board and the 4-pin plug carries the power back to the motor (two wires) and to the headlight (other two wires.)  This setup allows for easy decoder installation.

The tender wheels also pick up from the rails.  So they need to have the proper side-to-side orientation relative to the locomotive wheels.  Close examination will reveal that one end of each tender axle is insulated by a plastic bushing and the other ends connect electrically to the wheels.  When properly installed, the insulated ends of both axles in one truck are on the left side of the tender and the insulated ends of both axles in the other truck are on the right side of the tender.

And by all means, do as Mike asks and let us know how you make out.

[newguy]

Thanks guys! It worked! I really appreciate it.

Take care

[SteamGene]

As a general note, before I remove tender trucks from any tender that has wheel pick-up, I take a small paint brush and paint a stripe on the bottom of the tender across the axle, one truck on the fireman side and one on the engineer side.  That way I can't reverse them when I put them back on.  As long as the white stripe matches, tender bottom to axle, I won't get a short.
And yes, the USRA light Mountain is DCC ready.  It just came out before Bachmann put that on the box.  That's a very nice locomtive.
Gene

[newguy]

Thanks for the information. I really want to convert it to DCC. I've also noticed that as it goes around corners the loco will pull the front wheels of the tender off the track and then when the track staightens the wheels are pulled back on again. Does this mean that 18 inch radius is too small for this 4-8-2?

[Jake]

Thanks for the information. I really want to convert it to DCC. I've also noticed that as it goes around corners the loco will pull the front wheels of the tender off the track and then when the track staightens the wheels are pulled back on again. Does this mean that 18 inch radius is too small for this 4-8-2?

Well which hole on the drawbar is the peg on the tender in? My 4-8-2 heavy mountain does that when the it is in the hole closest to the engine. It works fine if it is in the hole that is farter back

[newguy]

It is connected to the back hole on the bar. I thought of that. If your heavy mountain does ok then I would expect mine to do ok as well.  Maybe I just need to play around with it and figure out what is causing the problem.

I also just purchased two new spectrum SD-45 Diesels online. Should they do ok on the 18 inch radius??

[SteamGene]

The USRA light should negotiate 18 " radius curves.  The USRA heavy will not.  Your problem is probably with the wire harness.  Keep the draw bar on the outside hole and push as much of the harness as you can into the tender.  It might be a good idea to add a little weight over the front trucks. 
Gene

[newguy]

Thanks SteamGene for the good info. I'll try it and let you know tomorrow how it worked. Do you know if the Spectrum SD-45 locos will have any problems on the 18 inch radius. All I have seen is pictures. I don't really know if they are longer than the bach gp-40s that I have.

thanks
newguy

[Jake]

The USRA light should negotiate 18 " radius curves.  The USRA heavy will not.  Your problem is probably with the wire harness.  Keep the draw bar on the outside hole and push as much of the harness as you can into the tender.  It might be a good idea to add a little weight over the front trucks. 
Gene

Well then, mine must not be an ordinary Heavy Mntn. Because it took 18" curves fine when I was breaking it in... PS, I have the J2 heavy mountain.

[tomcat623]

I have two spectrum sd45's, they work fine on my smallest radius (19.5)
they are great pullers, smooth runners too. what road are they?
Tom

[newguy]

Hey Tom,

One is a Great Northern and the other is a Northern Pacific.  I haven't gotten to the point where I am modeling certain roads yet. Right now I'm just collecting DCC locos. I want to be able to run 10 locos at a time with my digital commander.  I just keep an eye on Ebay and look for great deals. I compare prices to Wholesaletrains.com which is the most affordable site by far that I've found. I have gotten 6 locos from ebay so far. All but one were brand new and I've gotten everything 20%-%50 less than wholesaletrains.com.

When I eventually do a permanent layout, I know that I want to have a station with a rail yard with lots of trains lined up. Those seem to be my favorite layouts that I've seen personally and on the web.

Sorry, I know you didn't ask for my life story..

take care

new guy

[Jake]

Hey Tom,

One is a Great Northern and the other is a Northern Pacific.  I haven't gotten to the point where I am modeling certain roads yet. Right now I'm just collecting DCC locos. I want to be able to run 10 locos at a time with my digital commander.  I just keep an eye on Ebay and look for great deals. I compare prices to Wholesaletrains.com which is the most affordable site by far that I've found. I have gotten 6 locos from ebay so far. All but one were brand new and I've gotten everything 20%-%50 less than wholesaletrains.com.

When I eventually do a permanent layout, I know that I want to have a station with a rail yard with lots of trains lined up. Those seem to be my favorite layouts that I've seen personally and on the web.

Sorry, I know you didn't ask for my life story..

take care

new guy

Just so you know, you are going to need a booster for 10 train ops. Only because the easy command can only supply enough power to operate 4-5 trains at a time. But if you add a 5 amp booster, you can operate 10 trains just fine. Bachmann has in the past recommended Lenz boosters for the E-Z command, I'm not sure if that still stands with their new booster though.

[newguy]

hey jake,

Yeah I know I need a booster. I've got my eye on Bachmann's 5 amp power booster but I really don't know much about the boosters. Does anyone know if this will give me enough juice to run all 10 trains well?? Maybe Bach Man could tell me.

New guy