Hey All,
I got an ol’ gear driven Athearn GP-7 (GN shell) for like 7 bucks at a swap meet… I just love the GN logo and it runs fine (noisy!!) and I was hoping to remotor/gear it. I was gonna do an NWSL kit, new wheels, etc… but I wanted your all opinion… is this impossible? is it worth it? I enjoy learning things like this (will help me when I eventually tackle a brass beast some day…). Just would love your thoughts… have any of you done this one?
Brian
I’d say go for it![:D] Working on Athearns is a good way to get practice for later projects, and they can be really smooth runners. Just remember to get the right wheels if you’re re-wheeling (metal truck sideframes = outside frame, plastic = inside frame).
When you say “ol’ gear driven,” do you mean it has the old tower drive? Or is it just an older version of their more standard gearing?
Yes. For $105. you can get a ‘perfect’ chassis for it - that will equal any $100 chassis made - except it fits.
http://www.ppw-aline.com/custom_built_chassis.htm
OR you can acquire a used LL. P2K GP-9 and replace the gear wheels & axles. The NWSL wheels greatly inprove slow speed response.
In short, the old Athearn shell isn’t worth much.
The A’Line chassis and NWSL wheels will set a higher standard of performance for you to try and match.
It would certainly be good as a learning project and a good way to improve your skills, however, this particular Athearn model goes back almost 40 years and the body casting shows it by todays standards. The hood width is way oversize to accamodate the original oversize motors of the day and there’s not much you can do about it other than major surgery. You could check ebay for a FrontRange or RailPower GP-7/9 shell to mate to the chassis though. But if you can live with the wide hoods and want to learn by doing, I say go for it. You can always reuse the motor, wheels, etc in a future project as you gain more experience. Have Fun!
It depends on what you want. If you want a really accurate GP-7, I’d go with one of the alternatives (Atlas, P2K). If you’re looking at it as a project loco to hone your skills, then by all means, knock yourself out. I recommend replacing the motor, flywheels, and wheelsets. The gearing is fine, though you should get some NWSL thrust washers to eliminate the worm end-play.
This debate also came up a month ago: ANCIENT ?!? Athern GP 9 Kit. Can it be put to use?
I enjoy rebuilding Athearns. My recommendation (which echos other poster’s) is to replace the motor with a quality can motor. That alone will help tremendously.
On my engines I replace the motor, add NWSL wheels and Ernst slow speed gearing, and plant a Loksound decoder. Keep in mind that by the time I complete all of this I could have bought a high dollar engine from the hobby shop for the same money. But, it’s fun and I like to tinker. It’s all in what you want to accomplish and what you enjoy.
It’s not worth it if all you want is a loco. It would be worth it if the main reason you do it is to have fun messing around with small parts and making a junky loco run smoothly. I bet you really get a feeling of acomplishment when you finish too![:)]
If you want it to last forever, get a good sagami motor in it. If you want some experience, and don’t mind swearing at the engine a few times, work on it’s old motor to get it running nice and smooth. Yes, Athearn engines CAN run smooth.
Phil
Brian,
You only have about $7 invested. It will never be a ‘great’ engine, but it can be upgraded without spending a lot of money. Here are some simple things:
This will make a good running locomotive. The ‘wide’ carbody/rough details will never be outstanding, but you will get a decent ‘runner’ and the exercise will improve you modeling skills.
Jim Bernier
If you want to learn a new modeler’s skill then rebuilt the Athearn GP7 and the best news is it shouldn’t cost you a small fortune.This skill will help you clean,service or rebuild other brands.
Of course you could buy a P2K GP7 and will more then likely replace the crack gears*…The Atlas GP7 one needs to add the proper style horns and remove the incorrect side mounted horns.
I enjoy tweaking my drives regardless of brand…I perfer my locomotives to creep from tie to tie.
See:
http://forum.atlasrr.com/discussion/topic.asp?TOPIC_ID=45324
If you want to try the tuneup route first, here are two very good clinics.
http://www.mcor-nmra.org/Publications/Articles/Athearn_TuneUp.html
I agree with the majority of the posters here: go ahead and rebuild it. It’ll give you a good opportunity to learn some new skills, and help to build confidence so that you’ll not be afraid to tackle this kind of work. I rebuilt two of these locos many years ago, before the Atlas or Proto versions were available, although at that time, the rebuild was strictly paint and details.
Later, using Mashima can motors, I remotored the 403 and motorised the 76, which was previously a dummy. I eliminated the flywheels, as I felt that their contibution was minimal, and added more weight. I also kept the sintered iron wheels, and these locos run and pull great. While I seldom run diesels any more (the layout was timeshifted to the late '30s), I keep these locos, wide hoods and all, for sentimental reasons. Not only were they featured in MR’s Paintshop in Feb., 1980, but they were also the first step in a long list of paint jobs done for others.
Larry, I don’t know about the GN units, but I think that the side-mounted horn may have been standard equipment on the GP7s, with each road either using it or substituting one of their own preference. The TH&B’s geeps look like they came with the side-mounted ones, with all eventually getting 3-chime versions on the roof of the short hood. Some lost the side-mounted horn, while others, like the 73 pictured below, kept both.
If I was looking to buy a GP7, the Atlas ones would be my choice. [;)]
Wayne
Good response, Jim. Believe-It-Or-Not in my twenty-years experience with HO-Scale the only powered Athearn unit I ever owned was an SD9 and I was extremely unhappy with its running performance. All of the upgrades that you advocate in your response were written up in the hobby press after I got rid of both the powered unit and a dummy - not to mention about fifty bucks worth of detail parts which I never got around to installing. Had I been able to do anything to improve their performance I might still be in HO-Scale. These mods will upgrade this Athearn mechanism from “good” to “better” but its unlikely that there are any which will upgrade it to “outstanding.”
An acquaintance used to pull my dummy behind one of Atlas’ 1970’s SD24s and I might say this to Brian: if he is considering MU’ing this unit with any locomotive other than an old Athearn - and if this is important to him - he needs to be prepared that the over-wide hood becomes readily noticable beside a loke with a scale-width one.
I wouldn’t recommend the PPW chassis (at least the recent ones), unless it’s the only option. The motor is excellent, and the gearing is all tuned real well, but the flywheels are awful. I got an SD90 chassis about a year ago (back when they were only $90), and I had to drill five holes in each flywheel to get them balanced, and I had to replace a universal coupling. You also have to disassemble them for painting. A Line’s custom builder also takes about a month to get it built.
Any of the other methods mentioned will work very well, and will only cost about half what the custom chassis does.
Thanks for all the great comments… all of which are useful. I think I will try Jim’s suggestions…gotta visit the posted links first! I don’t need a perfect model, just some nice, shorter engines for my sons (4 and 2) to run on the railroad that will work well… And yes, at 2 and 4 they can BOTH control their own trains! Thanks again. I will post pic’s when done!
Brian
Darth, can you clarify the above about wheels? You lost me here… As for tower drive…no; I mean no fly wheeled version of the usual type (I think!).
Brian
I’ve actually done this before, learned a great deal in the process. One day I was bored and decided to see if I had enough parts to build an engine completely from things in my scrap box. A several hours later I had a fully functioning undecorated Athearn GP9. I had to fabricate a few parts, but in the end it worked out well. Now granted I’m not sure what I’m going to do with this engine, but I’ll find some home for it on my layout. The wide body would usually bother me and I’ve gotten rid of any engines with that problem that I’ve otherwise had (hence why my scrap box had so many Athearn parts) but this one I built myself and so it will be run, regardless of the rather toy-like proportions. Maybe as a SOO or CP unit.
Cheers!
~METRO
I’m sure Darth won’t mind if I jump in here, since he’s MIA. [oX)]
Brian, if your units are without flywheels they most likely have the old Jet 600 motor with the grey magnet ring, and diecast truck sideframes. The diecast trucks have the axle bearings in the sideframes, while the newer trucks have press-on plastic sideframes, with the bearings between the wheels. The Jet motors can draw an amp under heavy load, so they are not the best choice for DCC. They can be tweaked to run well, but are more suited to DC operation.
The older Athearn diesels with metal truck sideframes had their axle bearings mounted in the sideframes, so they’re “outside frame,” as NWSL calls it. The later ones (1980+) have plastic truck sideframes with the axle bearings between the wheels in the truck’s mainframe, so they’re “inside frame.”
OK, so it’s early 70s old, and not the really old ones. That’s when Athearn developed what became the standard drive for most diesels today. If you had the tower drive, it would be pretty obvious (the trucks look like they have a tall tower in the middle).