Trains.com

Subscriber & Member Login

Login, or register today to interact in our online community, comment on articles, receive our newsletter, manage your account online and more!

Eliminating engine growl

7212 views
23 replies
1 rating 2 rating 3 rating 4 rating 5 rating
  • Member since
    July 2006
  • From: west coast
  • 7,584 posts
Eliminating engine growl
Posted by rrebell on Friday, March 12, 2021 10:32 AM

Fiqured this has more to do with the moter than the mechanics so put it here.

  • Member since
    February 2002
  • From: Reading, PA
  • 30,002 posts
Posted by rrinker on Friday, March 12, 2021 10:50 AM

DC or DCC? What loco? I get hints from your other posts that this is a Stewart Baldwin switcher - I can't image how broken one of those must be to make audible motor or mechanical growl, based on the 4 I have. Those Canon motors are about as quiet as can be. 

 In general, such strange noises are caused by lack of lubrication, or something just so worn that it no longer spins smoothly in the bearing surface. A lot of the grease used in models gets hard after a long time not being used, so al older loco might LOOK like it has sufficent (and even too much) grease, but if it has hardened, it's no longer allowing the parts to mesh smoothly. If you get a NOS loco still in the box, or a used one that's been sitting for years - disassembly and cleaning out all the gears and putting a little (emphasis on a little) grease or gear oil on them is pretty much a requirement.

 The motor itself has bearings in each end. You REALLY have to be careful with the amount of oil here, the tip of a toothpick dipped in a light oil will put plenty on the motor - lack of lube there usually produces more of a squeal that varies with motor speed.

 If it's DCC, you can get a hum or a 'singing' if the decoder is an older one that doesn't support high frequency motor drive - also called "silent running" or "supersonic" depending on the decoder maker. Only way to fix that is to use a better quality decoder.

                                           --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

Moderator
  • Member since
    June 2003
  • From: Northeast OH
  • 17,200 posts
Posted by tstage on Friday, March 12, 2021 11:56 AM

I think and suspect that it's your decoder choice.  As Randy mentioned, some decoders will emit a slight buzz or growl sound and some do this more or less than others.  While TCS is my defacto for motor-only decoders, I've found that their M-series decoders emit a noticeable buzz at speed step 001, which usually disappears around speed step 010.  Since it's a non-sound decoder, I just ignore it as diesel engine noise.  All other TCS decoders I've purchasd are quiet.  The Lenz LE0521W decoder I have in my Proto 2000 S1 buzzes, too.

Tom

https://tstage9.wixsite.com/nyc-modeling

Time...It marches on...without ever turning around to see if anyone is even keeping in step.

  • Member since
    July 2006
  • From: west coast
  • 7,584 posts
Posted by rrebell on Friday, March 12, 2021 11:57 AM

Sorry, new decoder, and this happens in a lot of engines, even new. Might just be me, have super hearing even though I have tried to adjust it. At least I don't hear what I am told it is imposable to hear anymore and I can tolerate those anti pest plug ins now (used to have to leave the room as they drove me out).

  • Member since
    November 2013
  • 2,672 posts
Posted by snjroy on Friday, March 12, 2021 5:21 PM

Noise can also come from the base. Does your trackwork sit directly on plywood?

Simon

  • Member since
    July 2006
  • From: west coast
  • 7,584 posts
Posted by rrebell on Friday, March 12, 2021 7:36 PM

No, on cork on foam, no ballkast yet.

  • Member since
    September 2007
  • 49 posts
Posted by Ladder1 on Friday, March 12, 2021 8:58 PM

The generator sounds on some steam decoders can be very loud.  Acutally the loudest sound when unaltered. And it does sound like a growl or grinding noise

  • Member since
    July 2006
  • From: west coast
  • 7,584 posts
Posted by rrebell on Friday, March 12, 2021 11:57 PM

Non sound decoder, ran same in DC. They run perfectly but make sounds, some worse than others. In fact they all make sounds but a few are too loud.

  • Member since
    October 2006
  • From: Western, MA
  • 8,571 posts
Posted by richg1998 on Sunday, March 14, 2021 1:51 PM

Can you post a video or two?

Rich

If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.

  • Member since
    June 2007
  • 8,864 posts
Posted by riogrande5761 on Monday, March 15, 2021 7:37 AM

Your engine is probably growling because it's hungry!  Clown

Rio Grande.  The Action Road  - Focus 1977-1983

  • Member since
    November 2013
  • 2,672 posts
Posted by snjroy on Monday, March 15, 2021 9:04 AM

We can't really help you without being more specific. I suggest you identify the manufacturer, model, age and type of decoder if you want more specific responses. A growl sound suggests that it is a motor/driveline/gear issue. A decoder problem (or lower end decoder) would make a buzzing sound. If you have sensitive hearing, only higher end diesels will be super quiet, like an Atlas, Athearn Genesis, Bowser or Kato model (others as well, this is not meant to be an exhaustive list). Athearn BB, Roundhouse, lower end Walthers and Bachmann diesel models will likely make some unwanted sounds. BLI or Bachmann Spectrum steam (with side rods) would also be super quiet. For cars, plastic wheels are also quiet compared to metal wheels. I personally don't mind these non-prototype sounds but if you are willing to spend for high end quality, it's out there.

Simon

  • Member since
    July 2006
  • From: west coast
  • 7,584 posts
Posted by rrebell on Monday, March 15, 2021 11:10 AM

It is proubly a motor issue. One that I have apart is a higher quality cannon motor in a Stuart engine, this one I use as an example as it is the loudest and most annoying but runs super smooth on DC. Been using it to test old decoders as the body shell is easy to remove (latches are way worn down).

  • Member since
    November 2013
  • 2,672 posts
Posted by snjroy on Monday, March 15, 2021 3:13 PM

A Canon motor that becomes noisy under DCC, but that is quiet in DC operation, suggests that it is a decoder issue. 

Simon

  • Member since
    January 2017
  • From: Southern Florida Gulf Coast
  • 18,255 posts
Posted by SeeYou190 on Monday, March 15, 2021 3:47 PM

rrebell
One that I have apart is a higher quality cannon motor in a Stuart engine,

All I can share is my experience with Canon motors. All of my brass Sunset USRA locomotives have Canon motors, and they are truly fine and silent drives.

Although I have no personal experience in DCC, my gut-hunch is suggesting it is the decoder as others have said.

-Kevin

Living the dream.

Moderator
  • Member since
    June 2003
  • From: Northeast OH
  • 17,200 posts
Posted by tstage on Monday, March 15, 2021 4:00 PM

snjroy
A Cannon motor that becomes noisy under DCC, but that is quiet in DC operation, suggests that it is a decoder issue. 

Simon

I totally agree.  The Kato, Canon, and Buehler motors in all the Stewart diesels that I have are smooth & quiet.  I've found that some decoders are prone to buzzing or growling, while others a quiet as can be.

What decoder are you using in your Stewart?

Tom

https://tstage9.wixsite.com/nyc-modeling

Time...It marches on...without ever turning around to see if anyone is even keeping in step.

  • Member since
    July 2006
  • From: west coast
  • 7,584 posts
Posted by rrebell on Monday, March 15, 2021 8:44 PM

It growls without decoder.

  • Member since
    November 2013
  • 2,672 posts
Posted by snjroy on Monday, March 15, 2021 9:04 PM

Did you not say it ran smooth on DC? Or do you mean without a decoder on DCC?

Moderator
  • Member since
    June 2003
  • From: Northeast OH
  • 17,200 posts
Posted by tstage on Monday, March 15, 2021 10:34 PM

When is the last time you cleaned and lubed your locomotive?  Under-lubing or over-lubing can both make the drivetrain noisy.

https://tstage9.wixsite.com/nyc-modeling

Time...It marches on...without ever turning around to see if anyone is even keeping in step.

  • Member since
    July 2006
  • From: west coast
  • 7,584 posts
Posted by rrebell on Monday, March 15, 2021 10:39 PM

It runs smooth both ways, just has a growl, louder than my other engines.

Moderator
  • Member since
    June 2003
  • From: Northeast OH
  • 17,200 posts
Posted by tstage on Monday, March 15, 2021 11:59 PM

It can stll run smoothly but not have enough or too much lube, which will make it noisy.

https://tstage9.wixsite.com/nyc-modeling

Time...It marches on...without ever turning around to see if anyone is even keeping in step.

  • Member since
    October 2020
  • 3,491 posts
Posted by NorthBrit on Tuesday, March 16, 2021 6:08 AM

Hi  rrebell.     I hope it is sorted out soon.   It is annoying when things go wrong.

 

As an aside.   Here in the U.K.   Class 37 locomotives have a distinctive 'Growl' and have the nickname 'Growlers'   (obviously).   Modelmakers have included the 'Growl' in their models.  Smile

 

David

To the world you are someone.    To someone you are the world

I cannot afford the luxury of a negative thought

  • Member since
    September 2003
  • 10,582 posts
Posted by mlehman on Friday, March 19, 2021 9:22 AM

If you want to dampen the noise, try this. You know those magnetic advertisizing gimmes? They're thin and the material they are made from is pretty effective in dampening noise, plus they add a little weight. I've lined the insides of several shells with this stuff and it works pretty well.

Mike Lehman

Urbana, IL

  • Member since
    July 2006
  • From: west coast
  • 7,584 posts
Posted by rrebell on Friday, March 19, 2021 11:14 AM

Never heard of that, might just try as you can get a pack of them from Walmart for less than a buck and I just bought them, self adheasive too.

  • Member since
    August 2003
  • From: Collinwood, Ohio, USA
  • 16,229 posts
Posted by gmpullman on Friday, March 19, 2021 7:09 PM

mlehman
I've lined the insides of several shells with this stuff and it works pretty well.

I've opened up quite a few factory sound units and found a type of black fuzzy tape. Broadway seems to use it a lot.

https://www.amazon.com/Tesa-Fleece-Interior-Harness-Mercedes/dp/B017OECD7W/ref=sr_1_1?dchild=1&keywords=fuzzy+black+tape&qid=1616198772&sr=8-1

I bought some and found it to be quite handy for eliminating shell-to-frame "buzzing" and it is handy for other sound deadening and light blocking applications. It has a very good tack.

I could be wrong but maybe introducing more magnetic material may be counter-intuitive to eliminating an audio hum? I know the motor has a magnet but I wonder how sensitive the small speakers and unshielded wiring on a DCC sound decoder is?

Regards, Ed

Subscriber & Member Login

Login, or register today to interact in our online community, comment on articles, receive our newsletter, manage your account online and more!

Users Online

Search the Community

ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT
Model Railroader Newsletter See all
Sign up for our FREE e-newsletter and get model railroad news in your inbox!