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A friend has had a lot of issues with his Sunset second run Great Northern E7A and E7B. The gears were not meshing, causing poor operation and noisiness. Here is the fix he devised so the E7s  now run smoothly and quietly. He also recommends changing out the motor for better operation.

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Out of curiosity is this consistent on 2nd run units?  TBH, I have not run my 2nd Run PRR E7s as I don't have the layout for it yet.  I have a 3 rail SPS one that I picked up off this forum that runs extremely smooth from the 1st run in spite of some of the early design issues.  I also have a 3rd run PRR E7 which should share the running characteristics of the E8 and SD7/9.  The newer models have improved due to lessons learned.

Charlie, I think Scott told me there were changes between the first series and 2nd.  My 1st series 3-rail SAL E7 made a nasty noise going around 072 curves and then one of the universals broke.  Scott sent me parts so all is good.

I have since replaced the electronics with BPRC, removed anything that wasn't needed, and it runs fine now, just no sound (yet).  Plus I'm now running on 2-rail code 148 track and have much wider curves.  The Silver Meteor sure is purty behind that Mint Green E7.

Just a couple of questions and one observation.  First, what year(s) did the affected "second run" come out?  Second: in looking at the .pdf attachment, is the thrust washer 0.5mm thick, or 5mm thick?  (It's not clear on the scan.)  For the middle gearbox, does the author literally recommend cutting a washer in half radially?  How would you do that, and why since it doesn't change the thickness?

Last question for @GG1 4877... I don't have any E7s, but I did purchase a 3rd Rail FP7 of 2013 vintage with a very similar 4-axle drive.   I think mine qualifies as "first run," as it lacks the ball-bearing inserts in the truck sides, etc.  For the lack of a layout I have not tested it.  Shortly after these came out, Scott acknowledged that some units make a tapping noise because the inner dogbone that connects the fuel tank to the truck was a little too small (see below.)  What other "early design issues" plagued the first run, that I should be on the lookout for?  Great post, thanks!! 

(graphic below applies to FIRST RUN and was supposedly corrected in subsequent production)

FP7-UJOINT

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  • FP7-UJOINT
Last edited by Ted S

The first run arrived in late 2011 and the second run followed closely sometime near the end of spring 2012.  It was a while ago, but I do recall some modifications as a result of the 1st run units.  I'm not the expert on the design changes, but I will have to get mine out and look at the differences.  I'm just the research and graphics guy ... I usually don't involved in the engineering side of things.

After the E7s, 3rd Rail did the FL9 and they run extremely well.  My FP7s are 2 rail as is all my 3rd Rail PRR so I honestly haven't run any of them yet.  As I recall, the internal design appeared in the original drawings to be very similar between FL9s, FP7s, F7s, and FTs. The SD9 introduced the ball bearings which has continued on every diesel since then.  

I suppose I need to get that 2 rail test track up and running sooner than later

Phil - that would make them part of the 3rd Run.  I am surprised as it shares the same chassis with the E8, E6, & E5s of which have not had known serious issues. 

The "Train of Tomorrow" that Charlie mentions could be considered a run 2.5.  It shares a little more in common with the 2nd run than the 3rd. 

Yet another reason to get a test track set up and check my PRR ones out and report back. As I have mention my 3 rail E8s, E6s and E5 run flawlessly.  Haven't run the two rail E8 yet which should be identical to the current E7 in terms of engineering. 

Ted,

I have owned first run E7 since offered with no issues and have run them extensively. I also owned two of the FP7 and their drivelines have worked just fine.

The only item that affected the FP7 was a needed adjustment to the QSI decoder PID and BEMF settings.  That was accomplished by a firmware patch from QSI Solutions at the time.

Phil are you really supposed to cut the middle one in half as shown in the .pdf?  How would you cut something like a washer, and do it with precision?

Also, it seems prudent to dress the cut edges so that they don't scratch the worm or bearing surface.  Still not really sure about the purpose of this or why the middle gearbox would be treated any differently.  Maybe I'm misunderstanding the .pdf or interpreting it too literally?

I am in the same boat as GG14877, i.e. no layout yet. Has anyone spoken with Scott at Sunset about this issue? If so, what was his response?  For this kind of money I am concerned about the apparent lack of QA.

There is no lack of QA at Sunset.  Scott is very diligent with numerous trips to the factory (prior to COVID) as well as a lot of communication directly with the in-country engineering team which have been working on behalf of Sunset for many years.  Scott's project manager at the factory goes back to the days when 3rd rail / Sunset was still made in Korea.  They are a talented group of people when given clear direction and they do ask questions when needed.   

I have a total of 37 3rd Rail plastic diesels from 2012 on and I have yet to have to experience any issues.  This includes 1st / 2nd / 3rd run E7s, FL9s, FP7s, F7s, FTs, SD7/SD9, E8s, PAs, E6s, E5s and the F3.  The only issue I am aware of that was more common was the universals on the 1st run units and Scott made replacements available once that was discovered.   

While 15 are 2 rail and I have not tested them, the rest have been run at my 3 rail club and have performed flawlessly for long stretches of time.  In many cases I have both a 2 rail and 3 rail version of several of these locomotives.  The only one that had a minor issue, was a 3 rail ATSF E8a that got confused on the TMCC signal due to the challenges my club has with getting good signal strength on a 32'x40' layout.  It just needs a reset.  I don't see that as a design flaw.  

As was mentioned by Chris, the biggest issue with the 2 rail versions is getting the programming fine tuned on the QSI boards for optimal performance.  The upcoming GP7/9s in 2 rail and future projects will have Loksound so the QSI issue will be no longer. 

In short, I expect this to be an isolated issue.      

Last edited by GG1 4877

Replying to Ted's most recent question here is the information my friend provided: "You cannot go into that space without taking the worms off the shaft-as they are a  force fit- I did not want to remove them- the half washer -cut with a pair of metal shears -very thin and soft-cuts no problem-flatten any distortion. And clean any burrs caused by the cutting-insert in gear box-it's just a space-it's not going to wear-pack gearbox with high quality grease. I use Nano grease.  

@Jay C posted:

This is probably not relevant and, most likely isn't the issue.  Earlier models had axle gears that were 10.5mm in diameter.  Later models have 10mm.  Is it possible the model had the newer gears?  Other than diameter everything else is identical.

That sounds pretty important to me!  If you change the worm wheel but not the worm, and the mesh isn't perfect, I'm not surprised that you'll have poor operation and noisiness as described in the original post.

"Other than that Mrs. Lincoln, how did you like the play?" 

Last edited by Ted S

Let me add one more thing. The early diesels, 2007 to 2012 used a low quality grease that gets hard over time. My suggest to anyone is to clean out their gearboxes and put some nice new, Marine Grade Moly Grease. We now supply the grease to the factory for these to avoid this issue.

There was a gearbox change when we made the SD79 project in 2015. We've been using that gearbox ever since. In 2017 we starting using ball bearing axle ends which greatly improved performance and reduced friction from the past productions. I think the design is now sufficiently tuned up for our future Diesel projects, so we go with what works.

Nice to read the feedback.

 

 

@sdmann posted:

Let me add one more thing. The early diesels, 2007 to 2012 used a low quality grease that gets hard over time. My suggest to anyone is to clean out their gearboxes and put some nice new, Marine Grade Moly Grease. We now supply the grease to the factory for these to avoid this issue.

There was a gearbox change when we made the SD79 project in 2015. We've been using that gearbox ever since. In 2017 we starting using ball bearing axle ends which greatly improved performance and reduced friction from the past productions. I think the design is now sufficiently tuned up for our future Diesel projects, so we go with what works.

Nice to read the feedback.

 

 

Oh no! Not that crappy grease found in Weaver models diesels back in 2008-2010!

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