N-scale Atlas GP35 loud "gear noise" fixable?


As I've mentioned in other threads, I recently bought a pile of used Kato and Atlas EMD/GE locos. Most run great, but one older Atlas GP35 is noisy as hell. It sounds like, "Whhhrrzzzzzz . . . " Is this due to motor age, gear-lash, bearing-wear, etc.? Is it fixable? I bought a variety of track and wheel cleaning products, plus a bottle of Labelle 108 light-oil. If it's not fixable, I'll ask the seller for an adjustment or a refund.
 
I am not familiar with "N" scale locos, but what works for "HO" should also work on "N". First, it's time to roll up your sleeves and take a closer look. Take off the shell and see if it still makes the noise with the shell removed. If not, then there's something rubbing that is probably loose. If it still makes the noise, then get down close and try to determine where the noise is coming from, engine, front truck, back truck, etc. Track and wheel cleaning products aren't going to fix any noise. The LaBelle oil might fix a dry bearing. Personally I use LaBelle 106 grease on the gears in my "HO" scale models. It doesn't "spin-off" and get on everything else. Whether you use oil or grease, use it very sparingly.
You mention that it is an older used model. Used equipment is not going to be perfect. It probably just needs dis-assembly, cleaning and lubrication to get it back into top-notch shape. I believe that I read earlier this month that you are a "newbie". If you are planning on staying in the hobby very long, you should learn how to do this anyway.

Willie
 
If you have not read Ron Beardon's "Bearing Block Magic" article, it's worth a look. Originally published in N-Scale Magazine, the article describes a method for reducing noise in 4-axle N-scale locomotives.

Here is a link to a PDF of the article:

http://trainweb.org/passengercars/Bearingblock.pdf

I have performed the fix on two locos, and it worked well. Depending on the mechanism in your loco, it might help. Complete details are in the article.

- Jeff
 
I believe that I read earlier this month that you are a "newbie". If you are planning on staying in the hobby very long, you should learn how to do this anyway.

Willie

Thanks for all the advice! Yup, I already had to perform some diagnosis on another loco, and some repairs on brand new rolling stock. I give your tips a try. Thanks!
 
I have performed the fix on two locos, and it worked well. Depending on the mechanism in your loco, it might help. Complete details are in the article.

- Jeff

Thank you for posting that! That article is very interesting! I'll give that a shot as well. Thanks for your help!
 
Is the noise a squeal, or a zzzzzzzz noise? A squeal will likely come from dry motor bearings, which would make a lot of sense. The engines originally were built around 1992 or so. A zzzzz noise can be from a bearing block rotated out of line, or a truck installed backwards. On those engines, the line of gears in the bottom of the truck should be visible. One set of gears should be closer to the right side wheels, the other should be closer to the left side.
I've also seen a motor get jarred out of its mount, and the flywheel will touch the frame, making quite the racket.
 
I think it's all of the above! I have several problem locos. I think two or three "whizzers," and two "squealers." I suspect at least one is just buzzing the shell somehow. The squeal I just noticed today. It's intermittent; perhaps a squeal or two every once in a while. Still too busy having fun playing with my new MTS deliveries, so I haven't gotten to any engine maintenance yet. Thanks for all the tips!
 
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I just tried my hand at some loco surgery. I've narrowed it down to three Atlas GP35s which are "whizzzers" (I have two other used eBay Atlas GP35s which run/sound great!). I made a claim on two of the loud GP35s with the sellers, so we'll see how that turns out. The third one, I attempted to repair . . .

So, I pulled this "experimental" loco apart (it was the cheapest one), and on initial inspection, the trucks and internals appeared very clean with no visible debris. The bearing blocks appeared properly seated, and the trucks were oriented correctly. I then sprayed the internals with what I thought was a mild electronics cleaner (it contains trichloroethylene, which apparently is not safe for plastics). I'm going to go back in and try to "wash-out" any trichloroethylene residue with some isopropyl alcohol later.

Next, I put a single, very small drop of Labelle 108 light-oil on each worm-shaft assembly. I put it all back together, and the "whizzing" seemed to lessen by perhaps as much as 50%, but it's still louder than my other "quiet" locos. It did also, however, stop "screeching." When re-assembling the loco, I tightened the chassis nuts, possibly tighter than they were, so that may have helped to lessen the noise.

Now, I just re-read the "bearing block magic" article (thanks, Jeff!), and now I know what I'm looking at. I'm going to pull the loco apart again and give that a try. Then, I'll try to get a tiny drop of oil into the motor spindle (which I didn't do before). Next thing on my list is to get a proper set of tools for re-assembling these tiny things!
 
DISCLAIMER:

While my attempts to apply the bearing block fix were successful, you are on your own when you give it a try! It's not very difficult if you carefully follow Ron Beardon's instructions.

Let us know if it makes a difference.

- Jeff
 
Sounds like most of the N scale locomotives that were available back in the late 70's. They weren't very good back then. So bad that I had to get out of N scale and move on to HO.
 
Sounds like most of the N scale locomotives that were available back in the late 70's. They weren't very good back then. So bad that I had to get out of N scale and move on to HO.

The Atlas/Kato GP30/35 was one of the best running locomotives of its day, and still are darn good. I had a selection of them right up to the time I left N scale.
 
While my attempts to apply the bearing block fix were successful, you are on your own when you give it a try!

No problem! I'm actually excited to give it a try. Anything I inadvertently destroy will be part of my education in loco repair and maintenance! I didn't spray the electronics cleaner on the trucks (and, I'm guessing the Delrin gears are in the trucks, since the worm gear is metal). Are these the only plastic components we're trying to protect by using plastic-friendly cleaners and lubricants?
 
No problem! I'm actually excited to give it a try. Anything I inadvertently destroy will be part of my education in loco repair and maintenance! I didn't spray the electronics cleaner on the trucks (and, I'm guessing the Delrin gears are in the trucks, since the worm gear is metal). Are these the only plastic components we're trying to protect by using plastic-friendly cleaners and lubricants?
That, and the body shell, that will inevitably get oil slung onto it. There are also plastic drive shafts.
 
I re-opened the loco I first attempted to repair. I turned the drive shafts manually and didn't notice any oscillation, so I left the bearing blocks intact. I lubricated the drive shafts at each end with a small drop of Labelle 108 (last time I only placed a drop the worm drive), and cleaned all the wiper contacts with electrical cleaner (I just got back from the drug store and got some 91% isopropyl alcohol and some alcohol wipes). This time, I was able to shape the wipers correctly for improved contact. Lastly, I cleaned the wheels with my Woodland Scenics' Roto Wheel Cleaner (this thing works great!). I'd say the loco runs 90% quieter now with excellent conductivity!
 
Just to sum up the status on my problem locos, most purchased used from various eBay sellers:

• Atlas GP35 #1: Problem: Loud "whizzing." Self-repaired using Labelle #108 and electronics cleaner. Runs 90% quieter with a soft "whirr" that's barely noticeable.
• Atlas GP35 #2: Problem: Loud "squeal" at very low or very high-speed. Self-repaired using Labelle #108 and electronics cleaner; runs 100% as quiet as a new loco.
• Atlas GP35 #3: Problem: Loud "whizzing." Returned to eBay seller with return shipping paid, and a full refund (I over-paid for this one anyway).
• Atlas GP35 #4: Problem: Loud "whizzing." Returned to eBay seller who repaired it and sent it back to me; runs 100% as quiet as a new loco.
• InterMountain SD40T-2: Problem: Shell detaches; front coupler mis-aligned. Seller accepted my offer of a substantial discount, credited to my account.

All in all, every eBay seller settled any issues I had to my complete satisfaction. As I mentioned before, I kind of over-bought in my frenzy to acquire a nice stable of Southern Pacific-roadnamed modern diesels, so thankfully, the one I really over-paid for was fully refunded. I also bought two brand new (NOS) Kato SD45s with the SP "speed" logos for only $79 each, which of course, run great.

However, I also paid a premium for a Kato GE AC4400 which had already been custom-detailed with a UP patch, but now that I know how to do my own UP patches, I probably wouldn't have bought it. It's gorgeous, but of the four Atlas GP35s, two new Kato SD45s, Atlas SD40, InterMountain SD40T-2, and Kato AC4400, ironically, my favorite locos to run are still the Atlas GP35s in a MU'd consist pulling a bunch tank cars. The GP35s' short frames simply scale better on my not-too-wide radius curves, whereas the AC4400 looks a bit over-sized.
 



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