The good news is I put it back together and it works.... The bad news is that noise is still present in reverse It's much less without the shell though...but with the shell on, the noise (in reverse) is somehow the same the same than it was before I take it apart and clean it !!! FRUSTRATING.............!!!
No, I think this is proven and many people have stated that if these blocks are assembled incorrectly it will create noise. Yes, one pair of sides is smooth and the other pair of sides is what you call faceted. They have to match front and back. One can't be smooth against the frame the other faceted against the frame. The argument then becomes which side should be against the frame. I always don't remember and it seems no one has that answer so I try both! There's only two possibilities. There's another method to try and reduce the noise and that is to (Ron) Beardan'ize the loco. You can't do this to every loco but I think the GP-38 falls into this class. You can take a read here and it does discuss the bearing blocks. http://u18b.com/wp-content/uploads/2019/10/Bearingblock09.pdf
Since it only does it in reverse then is has something to do with the applied torque. Look to see if the motor moves at all when running in either direction. If you see is shift then there is the cause of the sound, not you just need the where. If it doesn’t move, then put the trucks on opposite ends. That way what was reverse is now forward and visa versa, if you now get the sound going forward the issue is the truck/s.
2 things come to mind here: With the shell off...loosen the 2 black frame screws about 1/4 turn each. Put it on the track and run it...without the shell. Does the noise stay the same ? If so...tighten the screws back that 1/4 turn and then finger tight. Put it on the track and run it...without the shell. Does the noise stay the same ? If the above shows no improvement I am going with the 'bearing blocks' as the problem. JMO
If it is a 4 axle GP38...it doesnt have 'u-joints'. 4 axle locos do NOT have 'u-joints'. 6 axle locos MAY have u-joints....but not always. If you are considering the 'nut' that goes in the flywheel a 'u-joint' that is incorrect. If you try the fix I posted just above this one and it doesnt help...I would try the fix MK posted a link to below. JMO
Another possibility is if any prior lubrication has become hardened over time. On a similar note, I've had extremely tiny foreign bodies get stuck in gears before that would cause all kinds of problems. Some of these were so small I could barely see them even with an opti-visor on.
So are you saying this is not to be considered a U-joint??? Because it's what I have in that engine.....
I think the bearing block should be installed with the smooth faces facing the half frames. Like this, the "faceted" faces somehow snap into some details of the frame:
A few years ago I purchased an Atlas GP15. It arrived on the coldest day of that year and before I ran it I made sure to wait until it warmed to room temperature and then put it on the track, it sounded like a coffee grinder. I lubed it, ran it both directions and nothing changed so I put it away until I had time to take it apart and clean and check everything. When I later did this it got a little better but not a whole lot. Again I gave up. Now that I'm retired and have the time, I took it out of the box, set it on the track and it ran perfect! I know of only two things that may have happened: 1) the lube finally reached everywhere it needed to go and fixed the problem or 2) the good train fariy came while I was sleeping and fixed it for me. I'm going with #2. Sometimes things have a way of working themselves out. As I told someone not long ago, I seem to be fixing a lot of things now, I'm just not sure how I'm doing it. Ralph
I think they get installed the other way but, again, I can't say for absolutely certain. It may even change loco to loco. That said, I've made installing them with the smooth side against the frame fingers a standard with all my Atlas locos. Nevertheless, if I ever purchase a loco and it has noise issues, I would likely include flipping the blocks to see what happens. Regarding the faceted sides possibly locking into something on the frame fingers, I've never spotting anything that looks like that on the fingers. That said, I also don't understand what functionality they might have with the brass spring fingers when installed the other way either. Maybe the facets are for ID purposes only? Something else that popped into my mind is if all the nylon(?) washers are in-place between the worms and the bearing blocks. I see two of them on the worm assembly pictured above (I'm assuming that's a picture from the loco in question?). Are they present on the other worm assembly as well? Regarding these washers, I have at least one loco where there was only one washer per worm assembly and they were on the far end of the assembly. I purchase most of my locos second-hand, so it's hard to say if they came from the factory that way or not.
Yes, all the washers are installed....I almost lost one yesterday when my tweezers decided to be uncooperative.....and I thought "I'm screwed" But I was finally able to find it, stuck on my brand new precision screwdriver set case (woo woo woo tools) https://www.amazon.com/woo woo woo-...ocphy=9016962&hvtargid=pla-943242262682&psc=1
Just to confirm, you're hearing a grinding-type sound and not a high-pitched, whining, dentist drill-type sound, correct?
I will record some audio files (forward vs reverse, and with vs w/o shell) and will upload as soon as I can
LOL, KleinTools happens to share the same first name with a well known hobby vendor who does not advertise here, so their name is blanked out with "woo woo woo". But the malformed link still gets you to the Amazon page (out of stock) for the product! Home Depot also stocks this screwdriver set online and in their stores (6 at my local store), at the same price. I highly recommend this set.
About the bearing blocks, next time I take apart an Atlas locomotive for maintance that has never been opened before, I think I will take a photo of the bearing blocks before removing them so I will know for certain which way they go when I go to reassemble it. For some reason I have not thought about doing that until now and I have in the past just made sure they all were facing the same way. As time goes by I will be able to see if they all come from the factory facing the same. I know that in the past I have found trucks with gears both to one side instead of opposite like they should be, but this was mostly when Atlas started back up with a new supplier. Ralph
Things have gotten less noisy as I age, too. It has saved both me and the oil can a lot of work. But when I adjust the television volume, everyone leaves the room...
