I am in the process of adding a sound decoder to my HO scale Bachmann Spectrum K4 and would like to replace the headlight bulb with an LED. I can't really tell from the exploded view how to get to the headlight and then the lamp PC. It looks like the boiler shell has to come off as well as the smokebox front. Anyone have experience in this and can make any suggestions.
-Bob
Life is what happens while you are making other plans!
Bob,
No Answer yet? Give this a shot:
To remove the shell, turn the loco over, in the center of the post for the draw bar you will see a screw and a small metal washer with two ears to hold the draw bar on. Remove the screw and washer. Now lift the shell up from the cab end and slide forward and lift off the frame. If you look inside the shell you will see a PC light board, this and the 1.5 volt head light seem to work fine, so I decided to leave it as is and not used the decoder to power the headlight. No directional lighting, but does stay lit in both directions.
Have Fun!
Frank
Frank,
Thanks, I will give it a try. Too bad Bachmann doesn't explain how to do this as it would eventually have to be done. I don't think the 1.5 volt bulb will last very long. I have 12 Volt LED's that I use for headlights so I don't have to use resistors.
farrellaa Frank, Thanks, I will give it a try. Too bad Bachmann doesn't explain how to do this as it would eventually have to be done. I don't think the 1.5 volt bulb will last very long. I have 12 Volt LED's that I use for headlights so I don't have to use resistors. -Bob
This is model railroading. Manufactures expect their customers to have MRR experience.
How many car companies tell customers how to change and engine?
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.
Well they DO tell you how to change a light bulb - though seemingly this basic task is beyond the capability of many car owners, based on how many I see with a headlight out. They tell you how to change a tire, too, but most drivers seem helpless without roadside assistence to call.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
The exploded view will show you everything to open the loco. Just study the diagram carefully and proceed slowly.
Be advised there will be a resistor on the PC board in the tender. I hear of many complaints about dim lighting in some of the Bachmann steamers.
I have done that with the Bachmann 4-6-0 and 4-4-0. My 4-4-0 had a 3mm diameter LED. The 4-6-0, a 5mm down inside the smokebox fed by a light pipe to the headlight.
The diagram is for the newest K4 with sound. Bachmann changes things quite a lot at times. No idea if this is what you have.
http://www.bachmanntrains.com/home-usa/dwg/dwgs/H844X-IS00.PDF
Maybe the below discussion might help.
http://www.bachmanntrains.com/home-usa/board/index.php?action=printpage;topic=23375.0
I tried the single screw under the drawbar and the boiler/cab doesn't seem to budge. I got the smokebox front off and found it has a 3mm LED on the pc board. I still can't get to the screws holding the PC board in place. I read some of the other forum links that Rich posted and they seem to offer some good advice. I plan to remove the Bachmann PC light board and hard wire the DCC decoders. I can put a 1K resistor in line with the white or blue wire coming from the decoder and that should take care of the LED as far as not overloading it. I may remove the light pipe for the headlight and put a SMD in the hole behind the headlight lens. Haven't gotten these parts out yet so I don't know what the space will allow.
As a side note; It would be nice if manufacturers would include instructions for replacing light bulbs as it isn't always an easy task to get to the bulb. The exploded view is not that easy to follow and you can spend a lot of wasted time removing screws and parts that don't actually provide access to the bulb. Just my thoughts here. I don't have a problem changing lights in my autos, even the dash ones!
Thanks to all. I will report back when I get this all sorted out.
It appears to me anyway, that a lot of these engines made now-a-days, are like a jig-saw puzzle,when it comes time to take them apart, seem's like they delite in doing that and instructions are useless, in most cases. Two days ago, I took apart a P2K SW9, just to paint the two black plastic guys sitting in the cab. What a project, that turned out to be.
Good Luck!
zstripe Bob, It appears to me anyway, that a lot of these engines made now-a-days, are like a jig-saw puzzle,when it comes time to take them apart, seem's like they delite in doing that and instructions are useless, in most cases. Two days ago, I took apart a P2K SW9, just to paint the two black plastic guys sitting in the cab. What a project, that turned out to be. Good Luck! Frank
I understand what you mean. I finally got the entire 'body' off the K4 with the removal of just 'one' screw as described by one of the other posts. Who would have known that one screw would remove everything? I now can procede with my project and will try a 1K resistor to the front LED. If that does't prove satisfactory I will put a SMD inside the hole up to the light bezel, once I figure out how to remove the light pipe. Thanks again to all.
I finally got everything out of the tender, pc light board and Bachmann decoder, and started to rewire everything to install two decoders; a Soundtraxx DSX (sound only) and NCE D13SR for motor and lights. I put a 1K resistor in line for the LED headlight and a mess of wires for the two decoders. I traced all the wires from the engine/tender connectors and everything works except the engine runs backward when in forward. I reversed the orange/grey wires to motor and it still runs backwards?? I fixed that in DecoderPro as well as getting both decoders setup and given the same address. The headlight is now at least 100% brighter although it is still orange/yellow?? Must be the light pipe.
I had picked up the sound decoder on Ebay for $25 so I thought it would be nice to have sound in the K4. The sound is OK but I won't ever do another dual decoder install for sound. When I have a spare $90 I will get a Tsunami for it.
Just wanted to update the progress of this thread and to thank all for your input and support.