# Rivarossi Steam Locos



## traveller1949 (Feb 7, 2011)

Hi Everyone,
I have a couple of old Rivarossi steamers with the old round motors in them. They ran quite well and smooth while on DC but I have since installed Tsunami sound decoders in them and although I have adjusted and checked and rechecked the values etc they tend to not run smoothly. Would it be that the old motors although they havent had a lot of use are not suited to having sound decoders installed. Can anyone give me a clue of what may be the problem. Thanks
Bob


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## onemanakid (Feb 22, 2011)

I am sitting looking at my old 4-6-6-4 and wondering how to put a decoder plus sound into it. After much surfing, I discovered Allen Gartners site and have managed to get the back off the tender. But the loco wiring has got me stumped. Several posts say the reliability would be improved by putting pick-ups in the tender. That I can manage. Can you offer any guidance on wiring up the loco? Thanks,


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## NIMT (Jan 6, 2011)

_*traveller1949*,_ sounds like either the motor is not completely isolated from the frame, the wiring is pinching the motor or the drive train, or the decoder is set up on the wrong settings, speed curve, start voltage, min voltage, max voltage. There are a lot of variables and the only way to set them all is to test change and test again and again till it's all right.
Be a little more specific on the problem and I will try to point you in a direction.

*onemanakid,* On any decoder install you need to make sure that the motor is isolated from the frame. The reasoning for tender pickups, is that on most older steam loco's it's hard enough to get the motor isolated but to also pull power back to the tender only makes it that much harder!
So from the tender wheels you will have red,black to decoder, to the loco you will have 4 wires gray, orange to motor and white, blue to the headlight and if you want anything else like firebox light, cab light or number boards a wire for each of those. They sell plugs that will allow you to still disconnect the tender from the loco for things like packing, moving and service.


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## gunrunnerjohn (Nov 10, 2010)

*onemanakid*, if you started your own thread on the issue, it would probably be a lot less confusing, it's hard to work multiple issues in one thread.


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## onemanakid (Feb 22, 2011)

Point taken, My first post, so please bear with me until I get the hang of the system. Problem;
How to isolate the "round motor" when it is bolted to the metal frame?
I have thought of using fibre washers each side of the fixing screws.
What do you think?


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## gunrunnerjohn (Nov 10, 2010)

I think we'd need to see pictures. You also need to have the screw shaft insulated if it goes through the frame.


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## traveller1949 (Feb 7, 2011)

I did use fibre washers to insulate the motor from the metal frame.
It seemed to do the job. 
I am currently away on holidays at the moment so when I get back home I will have to do more testing of the decoder settings although I have already spent hours doing this.


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## gunrunnerjohn (Nov 10, 2010)

Well, if the metal screws go through the frame and motor mount, they only have to shift enough to short out and you don't have an isolated motor any more.


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## shaygetz (Sep 23, 2007)

gunrunnerjohn said:


> Well, if the metal screws go through the frame and motor mount, they only have to shift enough to short out and you don't have an isolated motor any more.


When I did my cab-forward, I used some shrink tubing on the screw before I turned it in. It was a very short piece and, combined with the isolating washers, did the trick. My Big Boy is from the early 70s as well but was already isolated, just a matter of splicing a chip into the circuit.


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## NIMT (Jan 6, 2011)

You don't have to physically isolate the motor from the frame, you just need to isolate the electrical portion of it. Please post some picks for us if you would. I would hate for you to smoke a wonderfully sound chip like that!


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## traveller1949 (Feb 7, 2011)

When I isolated the motor from the frame, I first of all used a light sanding on the black paint of the motor then glued the fibre washers to the frame.
I then put a smear of glue on the fibre washer and attached the motor to the washer with the screws. However I made sure that there was no glue on the screws as after a couple of days I removed the screws. I also glued a washer to the bottom part of the frame for a little extra insurance just in case the motor may have moved slightly and touch the frame.
To firm up the motor even more I put silcone around the bottom of the motor ensuring no silcone accidently got inside the motor. I waited a few days after this before I ran the loco. All this was very time consuming but I did get there in the end.


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