Help identify what is connected to my Rivarossi Big boy


Iron Horseman said:
I compared and sure enough! If nothing else, the shade of green wire is pretty telling. I don't understand a decoder with only 3 wires, but many folks out there more clever than I.
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dccwiki.com

Hornby's Zero1 Digital Control System

Hornby Railway's Zero1 was the first Command Control system built around a custom microcontroller from Texas Instruments. The Zero1 name was chosen to reflect that it was a Digital system. Introduced in the UK in 1979, it quickly became a dominant command control system.
dccwiki.com dccwiki.com
 
Thanks for all the help guys, I noticed something weird today when I tested the motor directly. It would turn on and do like half a revolution but then stop and I could just hear the motor buzzing. Any thoughts on what might be causing this?. Maybe it’s just very dirty inside and needs a good cleaning? Thanks
 
HansKuster said:
Hi,
the electronic part with the grey condenser is a "Hornby Zero 1" decoder. Google it and compare the images...
That's the main reason why the Big Boy doesn't move.
You should either replace it with a current DCC decoder if You run Your trains digital or remove if You operate analog.

Regards, HansKuster
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Thanks for the information, how would I go about removing the decoder? I do have a Bachmann DCC controller but I don’t think I’m skilled enough/have enough experience to add a decoder and I like the simplicity of regular DC.
 
Josh123 said:
Thanks for the information, how would I go about removing the decoder? I do have a Bachmann DCC controller but I don’t think I’m skilled enough/have enough experience to add a decoder and I like the simplicity of regular DC.
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Hard wiring a new decoder is relatively simple, there are plenty of YT videos to show how it's done, to remove the old one simply de solder the wires to the motor, or simply cut them, and use the two wires to the motor on the new decoder, but seeing the state the motor is in, replacing the wires would be better.

Make sure however, that the motor is totally isolated, again YT is your friend on how to do that.
 
Josh123 said:
Thanks for the information, how would I go about removing the decoder? I do have a Bachmann DCC controller but I don’t think I’m skilled enough/have enough experience to add a decoder and I like the simplicity of regular DC.
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As near as I can tell from the diagram in the link below. It looks like the wire from the tender pick up (part 27) to the motor is still there. Find the where the power is picked up from the loco frame (possibly part26 on top of the gear box) and connect it to the other side of the motor (assuming the motor isn't already grounded to the frame on one side. Everything else can go away, except you might want to keep the suppression capacitor just because those old motors can be electronically noisy..

https://hoseeker.net/AHMRivarossiassembly/ahm4884bigboyinstr1971page3.jpg

PS. Can you spin the motor by hand, or does it also jam when you do that?
 
Iron Horseman said:
As near as I can tell from the diagram in the link below. It looks like the wire from the tender pick up (part 27) to the motor is still there. Find the where the power is picked up from the loco frame (possibly part26 on top of the gear box) and connect it to the other side of the motor (assuming the motor isn't already grounded to the frame on one side. Everything else can go away, except you might want to keep the suppression capacitor just because those old motors can be electronically noisy..

https://hoseeker.net/AHMRivarossiassembly/ahm4884bigboyinstr1971page3.jpg

PS. Can you spin the motor by hand, or does it also jam when you do that?
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Yes I can spin it by hand,
 
should these wires be connected somewhere?
Edit: now when I connect the motor to power it moves!.
IMG_4030.jpeg
IMG_4031.jpeg
 
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Iron Horseman said:
Is that one wire, or are there two?. I mean, does it go from the gear drive and loop through that notch over the front drivers. Or are there two wires coming out of the notch?

Boy I wish I had a locomotive like this I could just go grab and look at.
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2 I believe. The one that’s not connected goes to the second picture.
IMG_4032.jpeg
IMG_4033.jpeg
 
Josh123 said:
2 I believe. The one that’s not connected goes to the second picture.View attachment 171316View attachment 171318
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Ok, the one that is not connected is going to be your headlight. I believe you will find it should plug into that wire with the heavy black end from the other picture.

And for the other picture here is what "I THINK". Cannot be for certain. Anyone else please feel free to correct me.
To make DC one would separate the motor lead I marked in red from the red decoder wire and connect it to where the green decoder wire is on that brass connector. Hopefully there is some extra wire inside the tape that already does that, so all you would have to do is cut off the red decoder wire. Refasten the brass connector to where it was on the screw to the gear box.

I'm thinking the two tabs on top of the gear box is how they are tapping the frame power, where the tab below the gears is the power coming in from the tender.
bigboy wiring 1.jpg


And on other items, from the other picture I see the valve gear is hanging. That could cause it to jam and might be one reason the motor isn't spinning the mechanism freely.
 
Just a thought here. I have redone several old Rivarossi steams including one big boy and you will be much better off replacing that old motor with a new one. Next install wipers on the tender wheels and use a plug like mentioned to eliminate the drawbar connection. If using a sound decoder, speakers can be placed in the tender but you will need a 4 wire connector. Take your time with a project like this and the old loco will get new life.
 
Bigboy57 said:
Just a thought here. I have redone several old Rivarossi steams including one big boy and you will be much better off replacing that old motor with a new one. Next install wipers on the tender wheels and use a plug like mentioned to eliminate the drawbar connection. If using a sound decoder, speakers can be placed in the tender but you will need a 4 wire connector. Take your time with a project like this and the old loco will get new life.
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Thanks, I thought of that too but the only motor I see that would work is on eBay. The price isn’t bad but shipping to Canada is more than the product. Do you know anywhere else you could a motor for the locomotive?
 
Josh123 said:
That sounds interesting, so like one of these?View attachment 171506
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Not sure what motor that is but I've used Mabuchi FK 280SA 14,000 rpm 2mm shaft 6 pole motor double end shafts
Or Mabuchi SF266SH same specs just single shaft (on the bay for $2.25)


Had to go look and I actually have the Mabuchi SF266SA single shaft

I've used both of them on steam and Athearn diesel You might have to replace the Universal (diffferent shaft diameter)

When Mel Perry was still with us he did a number of that kind of steam engine He owned 18 Rivorissa cab forwards
had his own blog site http://melvineperry.blogspot.com/
 
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MikeGTW said:
Not sure what motor that is but I've used Mabuchi FK 280SA 14,000 rpm 2mm shaft 6 pole motor double end shafts
Or Mabuchi SF266SH same specs just single shaft (on the bay for $2.25)


Had to go look and I actually have the Mabuchi SF266SA single shaft

I've used both of them on steam and Athearn diesel You might have to replace the Universal (diffferent shaft diameter)

When Mel Perry was still with us he did a number of that kind of steam engine He owned 18 Rivorissa cab forwards
had his own blog site http://melvineperry.blogspot.com/
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Thank you for sharing, this sounds great. Great price too. Better than the $60+ the rivarossi motor would have cost.
 
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