Large Scale Central

Bachmann Spectrum 762 Motor Block

Problem Solving
#1

I have a Bachmann Spectrum No. 762

I want to disassemble the motor block to add a decoder. The case splits sideways but I can’t get it apart because the wheels are in the way.

Does anyone know how to do this or can provide a link to a video. I tried to search Youtube but I wasn’t able to find anything.

#2

Mark

http://www.bachmanntrains.com/home-usa/dwg/dwgs/LS%202-4-2%20(Chassis%20and%20Gearbox).pdf

http://www.bachmanntrains.com/home-usa/dwg/dwgs/LS%202-4-2%20(Connection%20Diagram).pdf

Hope that helps.

Edit, you will have to copy the URL and paste it into your browser.

#3

Go to Greg’s Web Site. Here is a start link and go from there to find other ways you may be looking for.

http://www.elmassian.com/index.php?option=com_content&view=article&id=251&Itemid=283

Also, can got this way in Greg’s link.

http://www.elmassian.com/index.php?searchword=motor%20block%20bachmann%20annie&ordering=newest&searchphrase=all&Itemid=24&option=com_search

Hope this helps. (http://www.largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-cool.gif)

#4

David Maynard said:

Mark

http://www.bachmanntrains.com/home-usa/dwg/dwgs/LS%202-4-2%20(Chassis%20and%20Gearbox).pdf

Looking at the drawing it appears I need to remove part # GB14 MT10 located in the bottom left of the drawing to remove the wheels to split the case. Does anyone know if these are screws or pressed in?

Picture of wheel retaining screw/pin attached.

#5

Screws, but I think you lost me. Why would you put a decoder inside the motor block with the motor and gears? Why not put it in the boiler or side tanks where it is out of harms way? (http://largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-undecided.gif)

Click Here

#6

I will put the decoder in the sand cone on top of the engine block.

Unfortunately the pickups on the wheels are wired to the motor inside of the motor block so I have to open up the motor block to disconnect the pickup leads from the motor and attached the motor leads from the decoder to the motor. Then I have to connect the pickup leads to the input leads of the decoder. There is also pickup leads from the front and rear wheels that need to be reconnected to the encoder too.

#7

Mark,

Are we talking about the same loco? The pickup and motor wires are plugged into the PCB on top of the motor block. I see no need to open the motor block or remove the wheels.

Click Here

#8

Mine does not have a PCB board. The two drive wheels have pickups on them that are wired to something inside of the motor block. The leading and trailing wheels are wired to tabs sticking out of the motor block. It seems that all pickups are wired directly to the motor inside of the motor block. This is my guess though it is possible that I am wrong. Any help is greatly appreciated before I end up tearing the motor block apart.

#9

David Maynard said:

Mark

http://www.bachmanntrains.com/home-usa/dwg/dwgs/LS%202-4-2%20(Chassis%20and%20Gearbox).pdf

http://www.bachmanntrains.com/home-usa/dwg/dwgs/LS%202-4-2%20(Connection%20Diagram).pdf

Hope that helps.

Edit, you will have to copy the URL and paste it into your browser.

Dave can you find a Connections Diagram without the PCB Board?

#10

Mark,

If you have an old 2-4-2, not the latest version, then I can help. I’m pretty sure the wheels on the plastic gear (original) version are just a press fit into the hubs containing the gears. All that stopped them falling out was the dummy outside frames and the thick flanges inside the rails!

Try pulling them out, or leveraging (carefully) with a screwdriver once the plastic outside frames and the rods are off.

#11

Pete, he has the Southern locomotive, not the old 2-4-2 loco.

#12

Pete Thornton said:

Mark,

If you have an old 2-4-2, not the latest version, then I can help. I’m pretty sure the wheels on the plastic gear (original) version are just a press fit into the hubs containing the gears. All that stopped them falling out was the dummy outside frames and the thick flanges inside the rails!

Try pulling them out, or leveraging (carefully) with a screwdriver once the plastic outside frames and the rods are off.

Thanks Pete. After realizing that I had to take drastic measures if I was to move forward I used the Dremel to make a slot in the head to try rotating it with a screwdriver only to find out it is made of plastic and is pressed in as you described. Unfortunately it destroyed that pin but I was able to remove the other pins and move forward. Now I have to create a replacement pin unless these are available to buy somewhere.

#13

I heard the guy Mark Demyan can print out anything … (http://largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-wink.gif)

#14

That’s Mark Dashnaw who can print out anything. Dave Bodner, here in the Burgh has 2 of them multidimensional printers too.

#15

David Maynard said:

Pete, he has the Southern locomotive, not the old 2-4-2 loco.

Dave,

The “Lyn” was a 2-4-2 too. I’ve had a couple of them - one was fitted with r/c gear. Here it (my loco) is on the cover of the UK Garden Rail mag.

#16

Mark Demyan said:

Pete Thornton said:

Mark,

If you have an old 2-4-2, not the latest version, then I can help. I’m pretty sure the wheels on the plastic gear (original) version are just a press fit into the hubs containing the gears. All that stopped them falling out was the dummy outside frames and the thick flanges inside the rails!

Try pulling them out, or leveraging (carefully) with a screwdriver once the plastic outside frames and the rods are off.

Thanks Pete. After realizing that I had to take drastic measures if I was to move forward I used the Dremel to make a slot in the head to try rotating it with a screwdriver only to find out it is made of plastic and is pressed in as you described. Unfortunately it destroyed that pin but I was able to remove the other pins and move forward. Now I have to create a replacement pin unless these are available to buy somewhere.

I assume you are referring to the pins holding the rods to the wheels? Yes - they are just a press fit in the wheel. I doubt you can buy one, but it would be very simple to make a replacement or find an alternative. A nail or screw with the right size head could be filed down to fit and then glued in place. If you can ease the remains of the pin out, you could make something to fit it that looked like the old pin. It’s nylon, I believe, and difficult to glue, but a tiny bolt could be run into it to hold a new ‘head’ on the shank.

I’d suggest calling Bachmann’s repair shop in Philly. They often have junker locos lying around and may be able to find you some pins.

#17

Pete Thornton said:

David Maynard said:

Pete, he has the Southern locomotive, not the old 2-4-2 loco.

Dave,

The “Lyn” was a 2-4-2 too. I’ve had a couple of them - one was fitted with r/c gear. Here it (my loco) is on the cover of the UK Garden Rail mag.

Yea Pete, that is the locomotive I meant.

#18

David Maynard said:

That’s Mark Dashnaw who can print out anything. Dave Bodner, here in the Burgh has 2 of them multidimensional printers too.

Of course Dave Bodner came through for me as he always does. I hope to have time in a few weeks to get the engine fully reassembled and running on the track.