Large Scale Central

Refurbishing LGB 2040 Crocodile (1990s era)

Modeling Motive Power
#1

Hello all,

I recently bought my first G scale locomotive: a 1990s 2040 Crocodile by LGB. Previous owner had it on display on a rolling road for fifteen years and barely ran it, so it needs a little cleaning up and maintenance to get back to work.

So, I decided to take it apart and do a deep dive into the insides. It’s in very good shape internally, and even had the original factory service manual with replacement fuse inside the main body! The only things that need addressing here are the pins that the doors are mounted too, since they’re starting to rust. I am thinking of replacing them with brass or stainless steel.

(I’d put a picture of the pile of parts here but I’m not allowed to embed more than one thing yet since I’m a new member.)

I took things apart until I was able to entirely remove the 2040-I motor block, which got disassembled and cleaned in warm soapy water to remove most of the old oil and grease. I don’t know if it’s an age thing or too much lube or both, but the whole assembly was slightly sticky.

After cleaning, the gears were re-lubed with a bit of Piko gear grease and the axles got a drop of oil. I discovered that one of the gray plastic crank arms is cracked, but not fully broken yet.

Three outstanding issues remain before I can put that end of the locomotive back together and repeat the process for the 2040-II motor block:

  • No idea what the red wire is for. Blue and yellow run the motor, confirmed with my bench power supply, but red doesn’t seem to be involved. Must be something for the lights?
  • The blue wire is frayed and down to a few strands where it’s soldered to the motor block. I don’t have a source for the old crimp connectors so I need to preserve this wire as much as possible. Easy enough to do with a solder sleeve and some new wire.
  • Lastly, the side rods are in bad shape. They’re sticky and turning funny colors:

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Does anybody have any recommendations for getting these back to their original shiny state? I’m comfortable with touching up the black paint accents if cleaning and restoration ends up removing them.

2 Likes
#2

I think doing what you are doing is a good thing, always nice to know what inside the motor drives and what condition they are in. Old LGB grease does get somewhat hard and loses its lubing needs for the gears, etc., so a re-lub is needed, plus cleaning the side rods, etc, plus a re-lubing is needed at this time. The other parts you talked about with the rust on them is common for these parts for and engine of that age, but if it was me I would lightly sand, or use steel wool and scuff then clean, wipe with a rust preventive and re install. LGB did make quality models and keeping then lubed will in most cases out last us all. I will add here that I have converted all my LGB engines to RailPro battery power, you won’t believe how smooth and slow your engine will run, it’s like a different engine with RailPro, check it out.

#3

Welcome Benjamin,
I know nothing about that locomotive. However if the side rods are aluminum you can probably wet sand them down. Start with 600grit to remove the crap then go to 800 then 1000 and if you want to get anal you can go 1500 or more. However I do not know the material and only guessing.

As for the wiring perhaps this helps.

#4

Welcome, Benjamin!

…

#5

i am not a sparky, but i never have seen any LGB, where blue and yellow run the motor.
with LGB always from the trafo/controller to the motor red is DC +, and blue is DC -.

i would take a second look, if it may be a non original rewired loco.

and be welcome!

#6

It could also be that I flipped the motor end over end when reassembling the motor block, which makes sense - right now I can’t power the motor from the tabs for the pickup shoes, but flipping it should make it happen. This makes more sense to me, but I’m not about to take apart my reference material (the 2040-II block) to see if I’m right…

#7

Soak the side rods in Dawn, or Palmolive dish soap and then use a tooth brush to clean the rods back to their original shine. The sticky is old oil and or grease.
Welcome aboard Benjamin

#8

Pretty sure the answers to the questions are in the wiring diagram I posted unless it is wrong and if that is the case…DO NOT CUT the blue wire!

#9

I cleaned up the side rods today. Hot water and dish soap didn’t touch the stickiness even after a ten minute soak. I moved on to some Simple Green all purpose cleaner and that knocked it off quick.

Some rubbing with #0000 steel wool later, and they’re much more presentable except for the black paint:

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Unfortunately, I think the pitting is here to stay unless I want to go nuts with sanding and polishing (no). They look great when held in the hand. I think the phone brings out the pitting and unevenness much more than is obvious in real life.

For touching up the black paint accents - does anybody know if the factory paint on these is gloss, matte, or in-between? The other pair of side rods are in worse condition and I can’t tell what the original finish is under the grime.

After seeing what the simple green did for the side rods, I’m going to take the gray crank arms off and give them another round of cleaning. Unfortunately, the cracked one is worrying me the more I think about it and I’d like to replace it, but can’t find a source for replacements.

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Further work will have to wait until I’ve repaired the wiring, as I don’t want to reassemble things until they’re good to go. That stuff is on order and will arrive eventually…

#10

Not sure why I’m surprised, but water-based acrylic paint was not a good solution for touching up the black accents:

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My plan was to “paint” the black accents and then knock back the extra with a razor blade. This would probably work better with light sanding/polishing the whole rod at once on a flat surface, but the rods are actually two pieces riveted together - I don’t have replacement rivets, so that’s a no-go. The acrylic did not bond well to the metal at all.

Lesson learned - I’ll grab some Testor’s gloss black enamel from Michael’s the next time I’m out and about. Hopefully that sticks to the metal better and be more resistant to handling.

#11

No luck in sourcing enamel model paint locally, neither of the two large craft/hobby stores near me had it in stock. It’s clear that the model paints are generally unloved and poorly stocked given how mixed up they were along with all the basic colors being straight-up missing.

So I did the next best thing and grabbed some Krylon Fusion gloss black spray paint…

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The weather is a little too cold if you follow the instructions to the letter, but I want to move on to other parts of this project. We’ll see how it responds to the tape coming off in an hour or so.

#12

Perfect? No, but certainly presentable from a (short) distance. I’ll clean up the edges with a razor blade once the paint has had a few days to fully cure.

Compared to how things started, I’m very happy with the results!

#13

That is what counts.

#14

The disassembled end is back together and still works!

Known issues are cracked housings for the lower lamps and a loose connection to the same lamps, causing them to be very dim.

Under no load I can get the axles spinning smoothly at a bit over 4V, pulling about 300mA of current. I’ve oiled the axles where they pass through the motor block housing, but I’m not sure if I should also oil the crank arms where they pass through the body shell since they are a loose fit. I may also oil the axle for the decorative driver the upper portion of the connecting rod attaches to.

I’m considering some plastic bushings for the side rods as it’s a loose fit and the clacking is very noticeable.

#15

I am now using Testors enamels in the small bottles, i get them at Hobby Lobby and Micheals. I do airbrush when needed, but for the side rods I would probably just brush them. On other note here, do check the gears on the axles, many of the older LGB engines the gears tend to crack on the axle. Remember many of these engines are 40 plus years old, just something that happens with the plastics of old. If your engine runs smooth then I probably wouldn’t replace the axle/wheels sets, but if you start to hear a thump down there, then the gears are not meshing correctly, and a replacement will be needed. I just purchased an LGB F-7 and the engine had a thumping sound in the truck; upon inspection I found a badly crack gear and the crack had spread apart and it wasn’t running correctly. I also inspected the other axles and found two more cracked gears, but they were running smooth. so I opted not to replace them at this time, $30.00 per axle does add up. Due note, the F-7 was pretty much new in the box and the wheels and sliders showed no wear, I’m saying old plastic.

#16

Yes, the Testor’s is the stuff I was looking for, at exactly those two chains. No luck at either, the gloss black was long gone.

#17

I was able to get the “Service Plan” document that I found inside the body scanned into the computer. Note the tape on the first page - that’s where the replacement fuse was kept until the glue gave up.

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2040-SERVICEPLAN.pdf (695.6 KB)

I have a full-resolution 40MB version but the forum won’t accept something that large.

Since I haven’t seen this document anywhere on the Internet, I’d like to submit the high-resolution version to Trainli and other archives - does anybody have points of contact or recommendations as to where to send the high quality version?