There are lots of resources for tweaking/adjusting/fine tuning Athearn locomotives. I don't ever recall seeing a discussion of the same subject for the vintage the Atlas/Roco GP/SD "yellow box" variety of locomotives. Anyone have a guess on why?
I wonder (specifically) if the Atlas can motors are more difficult to adjust and improve, or the improvement is not as great as with the Athearns, or both. (or neither)
Mike
Generally, and by the standards of the day, the Altas/Roco drive was considered pretty high quality. The reason Athearn saw so many mods is because to get a quality mechanism, you jacked the shell up and put a chassis underneath...well, most did reuse the frame, but other than that.
I think many of the older Atlas locos can be upgraded by installing parts from newer runs. That usually didn't help much with Athearn.
Mike Lehman
Urbana, IL
My guess as to the reason is, Atlas yellow box GP40's didn't need any tweaking or adjusting. Atlas has always had a reputation of being among the best running best quality (on the average) HO diesels of their day. I had several myself and they ran well and I didn't think they needed any tweaking/adjusting or fine tuning. However, when Atlas came out with their red box GP40's, I sold off all of my yellow box Atlas GP40's (mainly because the fuel tank looked like a blob of metal with slots in the sides and the new body looked better).
Jim
Rio Grande. The Action Road - Focus 1977-1983
Perhaps the three best things I did for an Atlas/Roco GP40 were #1 put a Bachmann GP40 shell on it (cut off the screw lugs and it's a drop-on fit) and #2 put in a PPW can motor and #3 put in a Digitrax decoder. For the most part most of my Atlas/Roco fleet are FP7's, one of which was fitted with an Athearn blue box motor, flywheels and shafts.
Dr. Frankendiesel aka Scott Running BearSpace Mouse for president!15 year veteran fire fighterCollector of Apple //e'sRunning Bear EnterprisesHistory Channel Club life member.beatus homo qui invenit sapientiam
The Atlas/Roco locos have can motors - they don't come apart like Athearn tan motors to do anything with, and the drive lines in them didn;t tend to have the flash on them like Athearn U joints. Plus they usually had wires for power pickup, not flat strips of steel.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
I have always liked these units. The fuel tank needs bondo but that is easy. I remove the light bar and add a long stick on weight the length of the long hood. For DC, a couple of 470 resistors and LEDs works real well.
Adjusting the sockets on the gear boxes in and out helps stop a buzzing noise going around curves caused by the drive shafts. One FP had a unbalanced flywheel. I did some testing once and grease in the gearboxes gave them a slower starting voltage on DC than oil.
The weakest link, if there is one, is the Roco motor. One F/M is a noise concern similar to a BB Athearn. This is caused by one of the pole windings having a partial short. The motor then becomes electrically unbalanced because one pole is weaker than the others. Roco upgraded this motor and left the sides open to help reduce heat when Con Cor marketed them.
This brings us to the best upgrade. The PPW / Aline motor is a nice replacement for a sick motor. I cut the old motor bottom off and use it as a adapter to attach the new motor into the chassis. The next one I do will be with a Kato motor.
Well, I got one at auction which had a Kato motor replacing the original (seller didn't know to say so!), and I think that's the way I'm going with 3 SD35s and 5 GPs. When I got it I was surprised at how well it ran; couldn't understand it until I opened the hood, then AHA! Part of my question was what was the general opinion on the can motors; I see it is "replace them". I have two ConCor GPs with open motors which run fine just as they came.
MS
As my experience goes.
My FP7's stock, run batter than any Athearn F unit
My Yellow box GP9s are perfect right out of the box with Kato drives
The s2 switchers, yellow and red boxes run great together or separately
Gp38's & 40s have a little to be desired in starting (yellow box) but are ok at speed and very quiet. I did sell off the lone Con-Cor GP38. Starting voltage was as bad as a stock Athearn & about as noisey too.
My Silver Series GP38's are a joy to run, smooth and quiet, and pull a ton. I've taken the dual mode decoders out and installed Tsunamis in a few, really sweet.
Love my Atlas RS2s (last run)
All in all, they are very good performers, with the exception of the GP38's & 40s under the Con-Cor name. Concor bought the tooling, but used a different motor, and the performance shows. Several of the Con-Cor versions did not last long at the club before they were replaced of remotored.
Karl
NCE über alles!
sanduskyWhen I got it I was surprised at how well it ran; couldn't understand it until I opened the hood, then AHA! Part of my question was what was the general opinion on the can motors; I see it is "replace them". I have two ConCor GPs with open motors which run fine just as they came.
If I may..I see no reason to replace the motors in my older Atlas/Roco S4s or SD24s since they are smooth runners anyway. Of course I never was a follower of such advice or useless new and improved modeling ideas. I certainly don't compare yesteryear's models by today's so called "standards" no more then I would compare a BB GP7 to a Atlas Classic GP7.
I would rather spend my hobby dollars on more needful things then replacing a perfectly good motor.
Some ConCor engines was equipped with the same Roco drives Atlas used and some had Kato drives.
Larry
Conductor.
Summerset Ry.
"Stay Alert, Don't get hurt Safety First!"
sandusky There are lots of resources for tweaking/adjusting/fine tuning Athearn locomotives. I don't ever recall seeing a discussion of the same subject for the vintage the Atlas/Roco GP/SD "yellow box" variety of locomotives. Anyone have a guess on why? I wonder (specifically) if the Atlas can motors are more difficult to adjust and improve, or the improvement is not as great as with the Athearns, or both. (or neither) Mike
Mostly 'cause the blue box Athearns needed tuning/tweaking/fiddling to run smoothly and quietly. The Atlas locomotives were beautiful runners right out of the box, and most of us figured we would never get 'em to run any better, no matter what we did to 'em. Whereas with a bit of tuning, you can make a blue box Athearn run a lot better than stock.
David Starr www.newsnorthwoods.blogspot.com
I had two of the Concor GP40's and those ran a bit differently. The Atlas/Roco would start well and run pretty smoothly but the Concor seemed to need a little help getting started, almost needed a push. Especially on a grade. Once the Concor was moving it ran smoothly enough, but consistantly had trouble starting.
sanduskyThere are lots of resources for tweaking/adjusting/fine tuning Athearn locomotives. I don't ever recall seeing a discussion of the same subject for the vintage the Atlas/Roco GP/SD "yellow box" variety of locomotives. Anyone have a guess on why?