After seeing davidmbedard's "forum plea" about the lack of helpful "how to" topics, I thought I'd post a "how to" topic on remotoring Bachmann's HO old-time 4-4-0 (older one with pancake motor).
This isn't quite the easiest thing to do, but it will give you a basic idea on how to remotor other tender-to-engine drives.
The motor I used for this project is a high quality Mabuchi FK-130SH motor, which is the same motor used in medium sized Bachmann Spectrum steam engines, and small Bowser switchers and trolleys.
Step 1:
I started by disassembling the entire tender. I clipped the motor wires so the old motor would come right out. The rear tender truck screw on mine is different because I bought it used, and the original owner lost a couple parts.
Step 2:
I took the shaft socket off the old motor, expanded the hole for the 2mm shaft, and cut the small part of the back off so it could go on the new motor a little farther. I then put the socket on the small shaft of the motor so I wouldn't have to cut any of the long shaft, and also so the solder tabs would be on the front.
Step 3:
I made marks on the frame the size of the motor's side to show where the frame needed to be cut. The motor needs to go right between the trucks. I then cut the unwanted sections out by drilling a series of holes and then cutting it out with an X-Acto knife.
Step 4:
I gradually opened the area with a file until the motor could slip in. The motor should drop 2mm below the frame to clear the shell. I also filed a rounded slot on the front of the frame to clear the shaft socket. The front of the motor is under the wood fuel load where there's more open space, so I raised the front of the motor 1mm so I wouldn't have to file too big of a slot in the frame. There's a plastic heat rivet, or whatever it's called, in the back of the tender shell, which holds the fuel load in place. This needs to be filed off for more clearance. The tender truck contacts and rear tender truck also need to be modified to clear the motor.
Step 5:
The light bulb on my 4-4-0 burned out, so I wired it to pick up with all the right side engine wheels, and with the left side tender wheels. The engine wire goes on the side of the motor with the blue dot, and the tender wires go to the side with the white dots. The tender screws had to be shortened to clear the motor. Since the rear tender truck originally had power going through the screw, I had to solder a wire directly to the leaf spring, and feed it through a hole in the frame.
Step 6:
The shaft going from the tender to the engine had to be shortened 5 or 6mm, so I cut that much off, drilled a hole going through the side of the shaft, and stuck a piece of brass wire in it to take the place of the ball coupling, although it would have been better to reconnect the ball somehow.
Step 7:
I reassembled the engine with the brass wire end of the shaft in the engine, because it seemed to work better that way. The new motor is lighter than the old one, so I filled the fuel load with lead to make sure it made good electrical contact with the track.
The 4-4-0 now runs at a more realistic 60-70 scale MPH instead of the old 150+, and is also much more powerful. It's also quieter, smoother, and has actual low-speed control.
Similar methods can be used for repowering other steam engines with this sort of setup. The results will be a smoother, quieter, more powerful engine.
_________________________________________________________________
The new ones have a better motor and don't need to be remotored. Electrical wipers really help.
http://www.pacificcoastairlinerr.com/bachmann_4-4-0/wipers/
Thank you if you visit
Harold
I remotered my J. Bowker 2-4-0 last year with the same motor, but it was an easier fit since those old AHM designs were scaled more closely to OO than HO. Depending on the diameter of the universal, you might be able to use brass tubing to splice the shaft together.
Nice work. Installing Harold's wipers on mine is on my to-do list as well.
Nelson
Ex-Southern 385 Being Hoisted
hminky wrote: The new ones have a better motor and don't need to be remotored. Electrical wipers really help. http://www.pacificcoastairlinerr.com/bachmann_4-4-0/wipers/Thank you if you visit
Good idea! Yet another way to make Bachmann 4-4-0s run even better!
I know about the newer version with a good motor, but I thought it might be a good idea to show how to replace a bad or cheap motor with a good one. It looks like they improved the gears, too! I'll have to look into those if I want another one.
SteamFreak wrote:I remotered my J. Bowker 2-4-0 last year with the same motor, but it was an easier fit since those old AHM designs were scaled more closely to OO than HO. Depending on the diameter of the universal, you might be able to use brass tubing to splice the shaft together.
I think the old AHM/Rivarossis were made larger so the motor would fit in there. I worked on one last year, and it had a fairly large square motor built into the tender.
Good idea. I'll have to give that a try and see how it works.
The stock Bachmann 4-4-0 has traction tires on both the left and right rear drivers. Darth, since your 4-4-0 is wired to pickup from the right side engine wheels, would there be a benefit to reconfiguring the drivers so both traction tires are on the left side?
Looking at how Bachmann wired these locomotives, it's not difficult to see why Harold's wheel wipers can improve performance (you get eight tender wheel pickup). Bachmann uses the front truck and one driver to supply power for the headlight. The motor is powered from just two tender wheels on one side and two tender wheels and a single driver on the other side.
It would seem logical that reworking the locomotive to pickup from four right side engine wheels and four left side tender wheels should also provide a significant performance improvement. Both methods extend the electrical wheelbase.
TwinZephyr wrote:The stock Bachmann 4-4-0 has traction tires on both the left and right rear drivers. Darth, since your 4-4-0 is wired to pickup from the right side engine wheels, would there be a benefit to reconfiguring the drivers so both traction tires are on the left side?
You would get one more wheel picking up electricity, so it might handle switches and dirty track easier. Mine seems to work fine on switches, so it isn't really something that needs to be done.
loathar wrote:You the man Darth! I was wondering if you could fit a better motor in those. I've got an old one I'd love to repower. You can shorten (or lengthen) those drive shafts by cutting a section out of the middle and inserting the ball ends into a correct ID peice of tubing. (brass or plastic) Just make sure it's straight and a good tight fit with a little CA.
I did this motor conversion in a couple 4-4-0 Bachmanns about three years ago. It works very nice. I use Harold's tender wheel pickup idea also. I close couple by shortning the drive shaft and couple both halves with a small piece of brass tubing. This can affect minimum radius for the engine. Moot point now but just before Mantua went out of business, I bought General tender frames and used the Bachmann tender housing. I installed Lenz DCC decoders in the rear of the tender.
rich
If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.
Wow, all positive response so far in a Bachmann topic!
I went ahead and did a little more work on the shaft. I re-attached the ball coupling, and it runs much better now. Because of where I cut it, I couldn't use brass tube to put it together, so instead I drilled a hole through the middle of the ball and shaft, stuck some brass wire through, and glued it all together. I don't think it's ever run so well since I've had it.