Atlas SW-8/9 Drive line noise---

I have 3 Atlas switchers to use on my modular switching layout. They all perform extremely well

However----all 3 emit a whining/growling noise at a certain low speed/low RPM. It varies among the three from barely audible, noticeable, and almost annoying. I have serviced the gears and bearings in the drive trucks but the noise remains unchanged.

All three locos are used with history unknown to me.

I am reluctant to remove the bodies just to snoop around looking for trouble. I am puzzled as to whether this is just a common trait for these switchers---or whether the growling whine is indicative of wear of the drive components. Loose or UNbalanced flywheels?

Your input is welcome---I know some of you have considerable collections of --and considerable experience with-- this particular model.

As an aside---is there any other 'O' scale switcher that performs so well at low speed? The Sunset 44 ton switcher runs a distant second, I believe?? -Salty Rails-

1/23/194:05 PM

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PRR ManOGR Forum Member

design-wise, the Atlas SW units and their driveline are very quiet runners. if you've already serviced the wheelsets, then it's time to open her up.

I'd check for a loose motor mount, or loose or unbalanced flywheel. also check the universals that connect the motor to the gear towers for binding.

I've also owned a Sunset 44 ton engine. The Atlas unit runs smoother in my opinion.

good luck.

1/23/196:37 PM

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RooOGR Forum Member

I just went around the layout after staging it for tomorrows running session and counted eighteen Atlas switchers rostered waiting for work.

Over the years some made funny noises others are completely silent and a couple just stopped running the ones that stopped running I replaced with new motors (I have plenty of spares). I guess I'm no help because when we run the layout it is so busy no one has the time to worry to much about the odd noise or maybe we just ignore it and keep going, tomorrow if I remember, I will see how they are performing as far as noise goes. We have very little trouble with these engines but then we don't run them into the ground day after day week after week for long periods.

Once a week we run the layout and then it's only switching moves and short trains all day long. I cannot remember anything breaking on them in regards to the driveline and I am sure I would remember because I'm the only one who does all the repairs!

I have modified the Steel mill locos some with Flat cab roofs, new DC wiring, twin headlights at the rear, flashing lights on the roof, some of the locos have NWSL wheelsets fitted (have had a couple of gears come loose on the axles) all are fitted with Kadees. I know one loco makes an intermittent "squawking" noise now and again can't think of anything else sorry I can't help you any further. Roo.

1/24/197:01 AM

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Mike CTOGR Forum Member DIGITAL SUBSCRIBER

There was discussion at one point about TAS speed control that continued to ERR drives. Electronic noise beyond what could be masked by engine/sounds.

1/24/197:55 AM

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RooOGR Forum Member

We ran eighteen SW switchers last Friday hard to believe you need so many but that's the Steel industry for you! ha Ha.

None of them made any annoying noise they all seem to have settled in to their new home one misbehaved.... broke a coupler, it had to be one I missed putting Kadee's on!

I don't know if you blokes believe me when I say we need so many switchers for the layout so here is a few photos as you can see I'm working on the layout at the moment building a crusher (First photo left side) for the Slag Reclamation plant have photos soon on the Steel mill thread.

Happy Australia day from Saturday 26th! Take Care Roo.