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 Posted - December 03 2006 : 5:40:08 PM
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A while ago I posted a pic of my PC (mehano) SD-35. GoininCirclez asked if it was the old athern or atlas or something, shell and drive. I took it apart to take a look and see why the motor was grinding. When I ran it with no shell it ran smootly and quietly.
There are two black marks, one on each side of the shell where I guess something is rubbing. I don't know how to fix it. Here are some pics of the motor.
Anyone know how to fix it?
-cheez
BTW-if its any help, the motor grinds because at its previous owner's house, it jumped the track and fell on the floor...
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Posted - December 03 2006 : 11:46:46 PM
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I have taken mine apart to see what might cause those black marks. No moving parts are there! That area is against the side of the motor. Are you sure something is grinding? Could it possibly be motor vibration passing to the shell? Check and see how much your motor can move in the motor mounts. Mine has some slight side to side rotation, but not much. Does yours move enough to make contact with the shell? Also, check and see if the PC board is screwed solidly to the tops of the motor mounts.
Looking at the 2nd pic, it looks like you might also have a red wire wedging between the motor and the shell. If so, that would pass motor vibration to the sheel and may also produce a buzzing noise. Try to keep all the wires tightly bundled together.
Edited by - Hypoponera on December 03 2006 11:51:23 PM
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Posted - December 03 2006 : 11:55:19 PM
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Because of the small diameter of the armature shaft , the weight of the flywheels can bend it if the locomotive is dropped causing vibration that may be causing the motor to chatter against the shell.
Put the loco on blocks and run it at low RPM. rest a pencil on the frame andd slowly move the tip tward the flywheel untill it starts to touch it. If it makes a mark all the way around the flywheel, it is not bent, if ti dosn't the shaft is most likely bent.
You may be able to bend it back and get it close.
Ray
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Posted - December 04 2006 : 5:36:38 PM
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| Well, I'm not sure which part is the flywheel, but I think that the black marks are in about the same place as the plastic cylinders at the end of the shaft.Also, the grinding is much more noticeble on turns so somethings gotta be rubbing. Not sure whether its the shaft or the metal part near the middle.
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Posted - December 05 2006 : 02:22:43 AM
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The big round brass thing is the flywheel.
I have a few older mehano locos. they all seem to make more noise in the turns. I quieted them down by cleaning casting flash off the drive shaft and universal cups and readjusting them.
The motor could be out of alignment from the sudden stop after it's trip to the floor. This could have the drive shaft pushed to far into the universal cup.
It's really hard to tell for sure without seeing it in person.
Ray
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Posted - December 05 2006 : 6:03:27 PM
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| Flywheel...big brass round thing...got it. It could be something out of alignment, but I'm pretty sure the noise is because of something rubbing on the shell. When I run it without the shell, it's really quiet.
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Posted - December 05 2006 : 6:20:19 PM
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I fixed the wires Hypoponera said were hanging down. When I put the shell on and ran it, then took the shell back off and ran it, it sounded pretty much the same. I can't remember quite how loud it was before, but it isn't grinding like it used to.
-cheez
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