DCC conversion of old locomotives

[jecorbett]

I am returning to the hobby after a long hiatus and have a good start on building my large dream layout. I am committed to using DCC for this layout but I have a good sized roster of old locomotives, primarily Athearn diesels and Rivarossi steam from the late 70s and early 80s that still run well. I have heard that older locomotives draw so much power that they can burn out most DCC coders. Can someone confirm if this is true or not. If so, are there decoders available that can handle the heavier current? Would it make more sense to replace the motors. I intend to add new DCC equipped locos to the roster as well but since my budget is not unlimited, I'd like to use some of my older locos as well. Suggestions please.

John

[rrinker]

Easiest thing to do it get a meter and test them. If the Athearns have the yellowish colored motors, they should be within the limits of a decent HO decoder. The older larger motors are a tossup and need to be tested. Rivarossi motors I don't think draw that much, if you still have the instruction sheets, they list the current draw on them, most were around 0.7 amp if I recall from mine. But again, the best thing to do it put a meter in line with a decent DC power pack and just check. Hold the wheels or the flywheel and briefly stop the motor and check the meter reading, with the throttle wide open. That's the maximum stall current of the motor. If it's 1.5 amps or less, just about any HO decoder can handle that. Some can manage as high as 2 amps peak, 1.5 amps continuous.


--Randy

[claycts]

Randy, a follow up question. Can you go to a "O" Gauge Decoder that has a larger capacity or am I all wet?
George P.
"No trains till after the car show"

[cacole]

On older locomotives, insulating the motor from the frame is likely to be the biggest challenge to installing a DCC decoder. Even recent Athearn, except their Genesis or RTR locomotives, require that you remove the motor to get to the lower brush contact and modify it so it doesn't touch the frame.

Even the least expensive decoders by Digitrax, Lenz, TCS, or NCE are usually rated for 1.5 Amps continuous and 2 Amps peak current draw, which should be suitable. The use of an O scale decoder would probably be necessary only on a really powerful motor such as the old Pittman DC70.

[MisterBeasley]

I have a number of old Athearn engines from the 60's. I was able to isolate the motors and install decoders in them. One of them runs OK, but the others just don't perform well enough to run on a layout anymore. I used Digitrax H123 decoders - the basic, cheap ones. Your engines may indeed draw more power, but I would just go out and get a cheap decoder and try it. I converted 2 of the old engines to dummies and I run them in consists.

You will have to isolate the motors, though. My engines also had horn-hook couplers, so I had to replace them with Kadees. This is another potential pitfall. Make sure the couplers are completely isolated from the frames, or you may short through the couplers.

This may be hard on you. I know it was on me. Those old engines were part of my childhood, and it wasn't easy to give up on them. What you should do, though, is try out a brand new engine. It will show you the way.

[Anonymous]

I have converted many many old athearn diesels to DCC. I have done it so many times now that it is second nature. It usually takes me 30-40 minutes for a normal athearn job. I have done a bunch of old steamers too. They take a little longer but no problem really. I use TCS decoders, if you play with the dither you can get almost any locomotive running to layout-standards. John, If you are interested in having some decoders installed just drop me an email.[:D]

[rrinker]

QUOTE: Originally posted by claycts

Randy, a follow up question. Can you go to a "O" Gauge Decoder that has a larger capacity or am I all wet?
George P.
"No trains till after the car show"

If it fits!

[Anonymous]

The older locos that I don't bother with converting are LL, Bachmann, Tyco, etc. that have the motor mounted on one truck driving only 2 or 3 axles. They usually have traction tires so only pickup current with the unpowered truck. On some of my old Athearns I used a DH-163 decoder to get the BEMF options that allow greater fine tuning and tweeking of the locos performance. It may not be cost effective to have to buy this higher priced (double the DH-123) decoder. I have a Digitrax Chief Radio DCC system with full programming capabilities so i can access all CV's to really fine tune loco performance. Some systems may not be able to do this, so that is also a factor in your decision to convert an older loco. I've been able to get almost every loco to perform acceptably, two (a Mantua Pacific and a Lionel Hustler) needed repowering and Rivarossi's (Challenger and Cab Forward) needed additional electrical pickup added. If you run into anything questionable , ask about it specifically either here or you may E-mail me [e-mail]. I have done quite a few conversions for others in N, HO, and S. I'm no expert, but I may have done a loco you are considering converting. I've had no complaints from the ones I've done for other people. I like to see people be able to use their older stuff. I have been modeling for 35 years, so lots of my equipment is vintage (older than dirt!)
Jeff Kerr

[Anonymous]

I should start by saying kudos on converting. I held out against DCC, finally converted, and would never go back.

You say the locos you're going to convert run well, and in that case, ditto to what's been said here. Test the motors, most decoders will handle 1.5/2.0 amps, etc.

Personally I've found that every loco I converted (steamers from late 70's/early 80's, Mantua and Rivarossi) simply didn't run well enough to merit the hassle of isolating the motors, etc. Then again, they didn't run well enough to hassle with under DC either, so I should have known better.

Long story short: it ain't that hard to do (even if you have to isolate motors) if the loco is worth it, but I'd take a long, hard ponder of what "worth it" is... If it 's not running impeccably under DC it's doubtful it'll do any better under DCC.

[Anonymous]

I converted a couple of Athearns from the 1980s and they have performed well. They're noisier than the newer P2K and Atlas stuff, but they run just fine on DCC.

[Janafam]

You can convert the old Athearn units, just talk to a hobby shop that can guide you to a DCC module with the correct Amp value. The old motors were power hogs. Scan the web and you will see installation instructions describing the motor isolation, done carefully, it is not a big deal. Good luck.