I model the early 20th century Nevada mine railroads so the Bachmann 4-6-0 and 2-8-0 is very useful to me. A lot of those railroads used Vanderbilt tenders so when Bachmann Spectrum came out with that tender as an accessory, I was very pleased.
it was designed for the 2-8-0, so I was aware of the known wiring problems in hooking it up the the 4-6-0. I rewired the tender so it would run with the 4-6-0 but when I ran it, it was clearly having electrical problems and ran very intermittantly. Stopping and starting.
Figuring it had something to due with my brilliant electrical surgery I took another Vanderbilt tender and put a decoder in it and hooked it up to a 2-8-0 that I know runs well with the stock tender. However, it ran just as poorly as the other did with the 4-6-0. So my question is whether there is a known wiring problem with the Bachmann Vanderbilt and whether there is a simple solution to the problem. Any thoughts and suggestions are appreciated. I plan on getting the 2-8-0 to run well first and then go after the 4-6-0.
Why Bachmann would not wired all of their locomotives so that all of their tenders would be interchangable remains baffling to me. Thanks - Nevin
From what I can tell the connections are the stanard bachmann 4 + 2 combination
The 4 wire is left pickup, left motor, right motor, right pickup.
The 2 wire is the headlights.
There should have been no need to rewire it and I'm a bit baffled why you did.
Don - Specializing in layout DC->DCC conversions
Modeling C&O transition era and steel industries There's Nothing Like Big Steam!
Sounds like an intermittent pickup issue and not an intermittent short.
I have some Bachmann locos. Some have the connectors under the loco cab. Some have the connectors in the front of the tender.
I had to switch the wires on the HO USRA tender to match my 4-6-0 because I had to use the two adapter harnesses that came with the tender. No issues.
If no solution here, I would join the Bachmann forums and ask. There are forums for different scales, many users of Bachmann products and company reps.
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.
DigitalGriffin From what I can tell the connections are the stanard bachmann 4 + 2 combination The 4 wire is left pickup, left motor, right motor, right pickup. The 2 wire is the headlights. There should have been no need to rewire it and I'm a bit baffled why you did.
My four Bachmann locos have the driver pickups on the two pin connector. The four wire is headlight and motor. I just check my locos with an ohm meter.
I have seen tender wiring issues a number of times at the Bachmann forums. There are some wiring diagrams if you search the HO foums.
The problem is that the wiring of the mother board is different for the 4-6-0 than the 2-8-0. Hooking the vanderbilt up to the 4-6-0 without rewiring it leads to a dead short. This is well known. Hooking up the 2-8-0 should work fine but doesn't.
[quote user="NevinW"]
The wiring on my tender was "almost" the same. The two adapters that came with the tender reversed all three functions requiring me to re-wire the tender.
I had to cut a trace on the PC board and install a 1k resistor for the loco headlight.
There was a 120 ohm resistor along with three diodes for the dimming of the headlight when the loco is in reverse when the locos had light bulbs, not LED's. The headlight would have blown after re-wiring and no 1k resistor. I traced out the complete circuit.
The tender I had was the older Bachmann DCC ready USRA tender probaly for the 2-8-0 that use to have real light bulbs, not LED's. I was mating it up with the small driver 4-6-0 which has connectors under the loco cab. The tender has connectors on the front which requires to two adapters.
One link I have from some time ago.
http://www.bachmanntrains.com/home-usa/board/index.php/topic,7439.0.html
The good news is that I was able to shoehorn a TCS Wow decoder with a Keep-Alive capacitor into the Vanderbilt tender without too much modification other than lowering the motherboard. Connected it to the 2-8-0 and it works great. Hoefully it won't explode as it is pretty tight in there. Love the sound, The TCS is really great. Now I'm going to try again with the 4-6-0.
congrats and I learned something new
The pin positions on Bachmann steam locos have been purposely made different from loco to loco over the years.
Some locos share the same pin positions, others do not.
It relates to a number of factors including type of headlight (LED or incandecent), sound or no sound, size/type of tender.
The following is some info I posted on here and the Bachmann board years ago:
If you're doing any more conversions in the future, don't disconnect the lightboard in the original tender from the engine. Remove the lightboard from the vanderbilt tender. Then disconnect the wires going from the lightboard to the tender trucks on the old tender, and then move the whole thing over into the vanderbilt tender. Hook up the old tender's lightboard to the tender truck pickups.
Lot easier than rewiring everything.
wjstix If you're doing any more conversions in the future, don't disconnect the lightboard in the original tender from the engine. Remove the lightboard from the vanderbilt tender. Then disconnect the wires going from the lightboard to the tender trucks on the old tender, and then move the whole thing over into the vanderbilt tender. Hook up the old tender's lightboard to the tender truck pickups. Lot easier than rewiring everything.
That is one approach, but I never cared for that because the boards are different sizes and mount differently, requiring you to "rig" the mounting of the swapped board.
It is actually easy to release the wires from the connectors and simply move them around to the correct position for the loco you are attaching to - done it many times now.
Sheldon
As it turns out, further reseach on the TCS website indicates that there is a known problem with Bachmann tenders where the tab that connects the wire to the rear truck of the tender gets bent upward just enough to make intermittant contact with the lightboard leading to shorts and problems. Good to know. I wish I had known this before I lowered the lightboard! So far there is no problem though.
NevinW As it turns out, further reseach on the TCS website indicates that there is a known problem with Bachmann tenders where the tab that connects the wire to the rear truck of the tender gets bent upward just enough to make intermittant contact with the lightboard leading to shorts and problems. Good to know. I wish I had known this before I lowered the lightboard! So far there is no problem though.
Interesting - I have over thirty Bachmann steamers and a dozen more of their tenders behind other locos - never had that problem yet.