Bachmann Online Forum

Discussion Boards => HO => Topic started by: mkurek on September 13, 2012, 11:43:36 PM

Title: DCC Onboard GP40 Grinding Noise
Post by: mkurek on September 13, 2012, 11:43:36 PM
Just received yesterday the Bachmann EZ Command Digital Command Control System with
DCC-Equipped HO Locomotive.  After putting the engine (GP40) on the track, I hear a grinding
noise from the engine.  I have a DC GP40 and it doesn't sound nearly as bad as the DCC engine.
Does anyone know about what this grinding noise is?  Should I send it back to Bachmann?
Thanks.

Martin
Title: Re: DCC Onboard GP40 Grinding Noise
Post by: union pacific 844 on September 14, 2012, 12:06:04 AM
i have new DCC Onboard GP40 and don't have Grinding Noises i would send it in if has a Grinding Noise
Title: Re: DCC Onboard GP40 Grinding Noise
Post by: mkurek on September 14, 2012, 09:41:48 AM
Hey Guys,

I took the shell off and tried to isolate the noise.  It appears the noise is electrical, not grinding, although similar.  The noise is subdued/less than with the shell off however, but I still hear it.  I have a GP40 on DC and it does not make that electrical noise.  This noise on the DCC GP40 occurs at slow/crawling speed, and gets masked as speed increases.
My question then is, is this normal operation for the DCC engine?  Is it common for the DCC engines
to have an electrical noise at very slow speed? 

Martin 
Title: Re: DCC Onboard GP40 Grinding Noise
Post by: Joe323 on September 14, 2012, 09:57:17 AM
Hey Guys,

I took the shell off and tried to isolate the noise.  It appears the noise is electrical, not grinding, although similar.  The noise is subdued/less than with the shell off however, but I still hear it.  I have a GP40 on DC and it does not make that electrical noise.  This noise on the DCC GP40 occurs at slow/crawling speed, and gets masked as speed increases.
My question then is, is this normal operation for the DCC engine?  Is it common for the DCC engines
to have an electrical noise at very slow speed? 

Martin 

Yes especially low end decoders.  For a quieter loco look for decoders that have "silent running" feature especially if you want sound equiped locos.
Title: Re: DCC Onboard GP40 Grinding Noise
Post by: Reinhard S on September 14, 2012, 09:59:18 AM
Hi.

The shell has the characteristics of a speaker enclosure that is why the noise is more pronounced with the shell on.  The noise that you are hearing at slow speed is indeed electrical.  It is caused by the DCC decoder that is built into the standard line (and some Spectrum) locomotives.  Replacing the decoder on the GP40 is more involved since it is hard wired to the motor instead of using an 8 pin plug.  There is nothing wrong with the locomotive and it should give you many years of satisfaction.

All the best.

Reinhard
Title: Re: DCC Onboard GP40 Grinding Noise
Post by: richg on September 14, 2012, 11:34:39 AM
If you are sure it is the decoder doing this, NCE makes a decoder specifically to replace Bachmann diesels on board decoders. It is called the Bach-DSL. The manual is shown in the link.

http://www.ncedcc.com/component/virtuemart/?page=shop.product_details&flypage=garden_flypage.tpl&product_id=51&category_id=13

Buy from.

http://www.litchfieldstation.com/xcart/search.php?mode=search&page=1

Rich
Title: Re: DCC Onboard GP40 Grinding Noise
Post by: Doneldon on September 14, 2012, 11:38:47 AM
mk-

I concur with all of the above suggestions and will add another: Put a couple of smears of plastic-safe caulk or other gooey material on the inside of the flat parts of your loco's shell. That will tamp the resonation of the shell and help to reduce the noise.
                                                                                                                                                                 -- D
Title: Re: DCC Onboard GP40 Grinding Noise
Post by: mkurek on September 14, 2012, 11:03:33 PM
Thanks for the great expert advice guys.  I am new to DCC so it will have to sink in.
I called my local model train store and he said it is normal for the Bachmann
to produce electrical noise at crawl speed. 

Have a great weekend!

Martin