ge ho 70-tonner noise

[edpb]

I started a thread on this problem on June 17 and then could not find the forum again.  Forgot it was Bachmann - hard to believe?  Well, wait until you are 84 yrs old. 

Rich, if you see this, my loco is the same as yours.  I got the shell off and found that without the shell, the loco runs very quietly, almost totally silent.  With the shell, it makes rattling/scraping noises.  It is hard to think of a reason for the noise, except perhaps the faint vibration that can be felt on the weight is amplified by the shell and starts the shell, windows, couplers, everything shaking.  I'm sure that the only parts of the shell that touch the rest of the loco are the two screw pads and three pads that touch the frame.

It seemed that perhaps the shell mounting screws were bottoming out before the shell was firmly fastened, but putting another turn on them did not help.

I put enough thickness of foam peanut between the weight and the shell so I could really smash it down, and that reduced the noise noticeably, but did not eliminate it.  It's still annoyingly noisy and would make it doubtful that it would make sense to try to add diesel noises to this loco.  If I can find some foam the right dimensions I will try filling all the empty space with it and see what happens.

BTW, it is not necessary to remove the couplers and it is difficult to put them back on.

edpb aka Ed

[dewey 1234]

i have two of the same kind the 20 tonner are very loud no fix that i know. i have put cotton in them put tape in no results good luck

[richg]

Right now I am suspecting a cracked gear. But. usually the loco will make a very slight hesitation if there is a cracked gear. Happened with a 44 ton I had.
The plastic shells are very good at amplifying any motor/gear noise as you know.
I am 71 so I know what the challenge is like. With Macular degeneration in my left eye, HO trains are not being modeled anymore All I can do is try to help others with what little data I have accumulated.
When I get home Monday I will try to take a look at my 70 tonner.
I have stripped a couple 44 tonners and the 70 tonner would be about the same. I used plenty of light an an Optivisor when I modified my 70 tonner a couple years ago.
I wonder where I left my lighted Optivisor?

Rich

[Doneldon]

ed and dewey-

I'd be very careful about putting things inside of locos which might insulate the
motor or interfere with air circulation. You could burn out the motor.
                                                                                                           -- D

[dewey 1234]

both of my 70 tonners  are brand new from bachmann.

[VTBob]

All 10 of my 70Tonners make this growling noise when they run. The shell amplifies the motor buzz like a speaker enclosure. I've not found a DCC-version that was quiet.

The old 2 motor versions were slightly quieter, but they all growl a bit.

Vermont Bob

[edpb]

To Dewey, Rich, Doneldon, Zytx --

Thanks to you all for your comments.  It's strangely comforting to know that all 70-tonners are noisy -- mine are normal after all.

I will be careful about stuffing the empty spaces.  If it works I will know it right away and after a short happy run I will check the inside temperatures.

Rich, it's nice to hear from you again.  I'm sorry to hear about your macular degeneration -- I know how that can go because it hit my mother-in-law some years ago, but even so I can't imagine what it's like to rebuild your life around things that don't require good vision.  I'm taking it as a good sign that you are able to continue on the forum.

Ed (edpb)

[richg]

To Dewey, Rich, Doneldon, Zytx --

Thanks to you all for your comments.  It's strangely comforting to know that all 70-tonners are noisy -- mine are normal after all.

I will be careful about stuffing the empty spaces.  If it works I will know it right away and after a short happy run I will check the inside temperatures.

Rich, it's nice to hear from you again.  I'm sorry to hear about your macular degeneration -- I know how that can go because it hit my mother-in-law some years ago, but even so I can't imagine what it's like to rebuild your life around things that don't require good vision.  I'm taking it as a good sign that you are able to continue on the forum.

Ed (edpb)

Close up work is not possible much anymore and can be frustrating.
I started working out every day and have taken up bike riding a couple years ago as there are about thirty miles of rail trails in my area and I find a lot of old railroad sites around me, plus one rail trail runs right next to the Pan Am Railway mainline so I see occasional rail traffic. I pick up my bike and cross to another rail trail.
Pioneer Valley Railroad, a 16 mile short line is about ten miles south of me.
Life is great.

Rich

[edpb]

Well, Rich, you must have plenty of beautiful trails to follow.  Your neighborhood has so much wonderful scenery,  I got my first look at Massachusetts on July 4, 1945 from a NYC coach on the B&A RR, going  from Green Bay, WI to Worcester to start my freshman year in college.  Those train trips in the middle 40's were wonderful, even in coach.  The trains were full of college kids and returning veterans, pulled by Hudsons or Niagaras, and then the PAs.  When the train pulled in we watched for smooth side or streamline coaches to get on.  We complained about having no place to sit, but we sat on suitcases or leaned on seat backs and talked, played cards, sang songs all through the night.  Happy days -- after my first trip the war was over and the future looked bright.

Ed

[bmjcook]

Gidday Ed
                I had great success quieting-down my older Athearn locos by gluing, using Silastic, very thin pieces of lead to the inside of the body wherever I could fit them. Don't ask me why or how it worked, but it did the job!...Cookie

[edpb]

Hey, Cookie, thanks for the note on your experience with quieting.  I will try it sometime during the next week and post my results.  Here's hoping --

Ed (edpb)

[faraway]

Like so many of us did I spend another evening with my little friends and tried to teach them to stop screaming on the layout.

I think it can not be stopped because the worm drive is designed in a way that the gear wheel and the worm do not have a fixed defined engagement. The truck is semi free swinging in all three dimensions. I can see severe damage at the top plastic gear wheel caused by the metal worm when the distance becomes to great. You can force that situation if you put only one truck on the rails and let the motor run. The free truck will fall down and partially disengage from the worm. Some of my engines disengage completely in that case. The top gear wheel is close to completely damaged in that engines.

[faraway]

I had a look at the trucks and the drive of the 44 ton switcher. the design is identical to the 70 ton switcher. However, the trucks are much more fixed. They have no horizontal or vertical mash. They can only rotate and swing. The top gear is not damaged at all by the worm.
I checked the measure of both trucks (44 and 70 ton) and the bodies but could not find remarkable differences. At a last try I installed the 44 ton trucks in the 70 ton switcher. That works fine but the noise is not reduced even they have a tighter fit at least does the metal worm not slip and destroy in the gear.
The 70 ton trucks with the damaged gear got installed in the 44 ton switcher. The 44 ton switcher runs as it does before. Not quiet but with acceptable noise.
May be I should consider it a helpless situation and my four 70 ton switcher noisy toys not useful for a model layout
Bachmann has made great progress with the drives in the new GP7/9 units. I hope they will rework the 70 (and possibly 44) tons drives some time too.

[faraway]

After all the tries and frustration last night I did think again what is the difference between the 44ton (a noisy drive) and the 70ton drive (an awful noisy drive)? It is  that the 44ton truck can swing and turn while the 70ton truck can also slip forward and backward and to some degree up and downward.
An Evergreen strip #104 (0.010 * 0.080) stopped the for- and backward move and reduced the noise by some degree. The 70ton noise is now down to the 44ton noise level.