Having trouble with Aurora F7s

Doug Quaid Jul 24, 2020

  1. Doug Quaid

    Doug Quaid TrainBoard Member

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    I had two sets of N gauge trains back in the early 1970s when I was a child.

    My dad made a Scenic and Relaxed layout for me, without all the sidings and switches.

    I had this one:

    [​IMG]

    and I had this one

    [​IMG]

    I was fortunate enough to find both sets NIB recently on ebay. Well, the Aurora set was in the shrink wrap and the AHM set was unused but no wrap.

    It was the strangest thing, I just started thinking about them and looked them up on ebay. Found them both immediately and both auctions were just about to end, the Aurora set only had about 5 minutes left. So I snapped them both up.

    Anyway,

    The AHM loco runs as badly as I expected. It never worked good when I was a kid either. It will go around the track but it's weak and stops once in a while.

    The Aurora F7 actually runs like a champ. I remember that from when I was a kid as well, the F7 was a workhorse and never gave me any trouble.

    Since the F7 runs so nice, I bought five more of them off ebay, with the Penn Central shells.

    [​IMG]

    I took all of them apart and carefully cleaned them.

    The Santa Fe F7 came right out of the factory sealed box, and was pristine and ran great both before and after cleaning.

    The batch of Penn Centrals were not factory sealed and they ran badly both before and after cleaning. They had a lot of oxidation on the brass parts of the motors, like they had been stored in a basement.

    When I use the Penn Centrals, the motors seem to spark a little and they surge in speed, the speed increases and decreases.

    Is there a trick to making these run good? Any suggestions? Any Aurora F7 gurus out there?

    I wouldn't mind getting the AHM loco to run better as well.

    Thanks in advance for any help.
     
  2. Hardcoaler

    Hardcoaler TrainBoard Member

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    You might want to look real close at the commutators on the motors in the PC units. Sometimes the tiny gaps between the poles get clogged with crud and will contribute to sparking as the motor brushes move between them. Also, have you removed the brushes to take a look at them? You might want to dip these in some rubbing alcohol and wipe them.

    Yes, Minitrix/Postage Stamp made great stuff. When I was a kid I painted a Trix F in C&NW to haul my Arnold Rapido gallery cars around the layout. My paint job wasn't that good and nobody made C&NW decals back then, but I hardly cared. :)

    Oh, this diagram may be of interest to you:

    [​IMG]
     
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  3. MK

    MK TrainBoard Member

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    Deoxit is your friend in these revival attempts.
     
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  4. Doug Gosha

    Doug Gosha TrainBoard Member

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    Old motors are most certainly going to need attention. A thorough cleaning of the commutator and brushes, as Hardcoaler indicated, will do wonders. Get all the gunk off/out. You can use Deoxit but make sure you get it all off as it has petroleum distillates in it which you do not want on the brushes.

    When finished, the commutator plates should be a nice, shiny copper and the slots between the plates completely clear of anything. Clean nthe brushes with 90% or better alcohol.

    If you know all this stuff,I apologize for the repetition.

    Doug
     
    Last edited: Jul 25, 2020
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  5. brokemoto

    brokemoto TrainBoard Member

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    I never had the Aurora/TRIX F-unit. I did pick up a few of the Q1b steam locomotives for five bananas apiece at a show. Every one of them fried their motors after only a little bit of running. They do not run well and as far as I know, they can not be made to run well. I took out the fried motors and put them in front of powered boxcars. They freewheel nicely. The one thing that I do not like is that the connecting rod pops in and out of the leading edge of the cylinder.

    That Q1b is yet another case of a manufacturer's selling a locomotive in all kinds of roads except one that actually had one. The Q1b is a Reading Company commuter locomotive. AHM sold it in Penn and ATSF.

    The Atlas/RR FM five axle is another one. Penn, ATSF, SP never had them. NYNH&H, NYC, LIRR and at least one of the major Canada roads had them, but Atlas/RR never sold it in any of those roads.
     
  6. Doug Gosha

    Doug Gosha TrainBoard Member

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    I got my two Q1B's to run acceptably by loosening things up a bit and lubricating them well. Same with my AHM FP45. The main problem with the Lima-built locos is the poor fit of gears on axles/studs and gear mesh. Mechanism binding, in other words. Free that up and the motor doesn't have such a hard time turning things. Same as with any loco.

    Doug
     
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  7. Doug Quaid

    Doug Quaid TrainBoard Member

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    Mine run okay-ish

    how do you go about "loosening things up"?



    where would I get a powered boxcar?

    that is a great idea
     
  8. brokemoto

    brokemoto TrainBoard Member

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    Ya' gotta make 'em. It shall remain to me one of the minor mysteries of N scale why no one ever has sold a powered boxcar or powered baggage car.

    The first decently running N scale locomotives were too expensive to use them for such a project, but, when the LL F-units and plastic frame FA-2s appeared, they were inexpensive enough that if the project came to grief, I would not be out so much money. My first one was a LL F-unit plastic frame chassis with an Atlas fifty foot Texas and Pacific boxcar jammed onto it. It had about the same throttle response as a Kato electric steeple cab that I had. The Kato was prone to stalling, so I hardwired the powered boxcar to it and received two improvements for my trouble. The thing could pull every piece of rolling stock that I owned up a fifty per-cent grade on a five inch radius curve and never stalled due to loss of electrical contact. It did stall on dirty track, but, anything will stall on dirty track. It required a minimum of work to the chassis and the boxcar shell. Most of it involved trimming the weights on th e LL and adding some shims to level off the boxcar shell. I made a few more like it on FA-2 and F-unit chassis. The FA-2 chassis required more work as it is longer than is the F-unit. It did not look the best, either.

    When LL did its massive market dump several years later, you could buy A-B pairs of metal frame FA-1s in the less popular roads for twenty or twenty five dollars the pair. The FA-1 was better suited to the fifty foot boxcar. As I was not going to use the shells, I did not care what the road name on the locomotive was. I bought two A-B pairs and four Atlas fifty foot boxcars and went to work. It required a minimum of work to the boxcar shell; mostly adding shims. I did have to glue a piece of Evergreen styrene to the inside wall of each end of the boxcar so that I could screw in an MT coupler. The LL metal frame FAs had body mounts to the shell. The plastic frame F-units and FA-2s had truck mounts. I dd not screw in the posts for mounting the couplers, as most of the force is against the wall, anyhow. The glue serves mostly to keep the post in position. Generally, I shy from using glue for coupler mounts, lest the force pull apart the glue joint. My shop teacher used to say that a "good glue joint is stronger than the wood itself", although I do not know if that applies to plastic.

    As a result, I now have four powered boxcars that push around my old small steam locomotives that fried the motors. I use the Q-1b, the LL 0-6-0T, the old Atlas 0-6-0T (Roco?), the very old B-mann 2-8-0 that I made into an 0-8-0 (the old Reading 2-8-0, not the SPECTRUM) ad a TRIX 0-6-0 (I bought that one with a fried motor at a show). You could also do this with the K-4. MP sold some old K-4 chassis without the motor several years past. I bought a few of them. I had the shells, so I put them onto the chassis and was pushing them around with the powered boxcars. I finally sold those K-4s, though All of those freewheel well when you remove the fired motor and some, but not all, of the gears. You must add weight, as well. The weight does not really bother those FA chassis, as they will pull anything.

    Some of the other older steam locomotives will not freewheel. The RRs will not, the C-Cs will not and most of the B-manns will not. That is a shame for the 0-4-0T and 0-4-0 and tender as well as the older versions of the USRA 0-6-0, as they have the old B-mann horrible, prone-to-frying motor, which would make them ideal candidates for this. For the 4-8-4, it is not that big a deal.

    They also work well to push around that old Davenport industrial diesel that several manufacturers offered in out-of-scale versions. All of those had prone to frying motors and ran horrbily. The latest plastic box version from B-mann is not bad, though. I had a pair that I hardwired together and they were pretty good. I ended up selling them, as well.
     

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