Bachmann 4-8-4 Disease

Hello,
My recently purchased engine ran well for a few minutes, then went all to hell. The two rear drivers would not keep their rod alignment, and the rearmost appeared to be separating in the middle of the axle. I remember the dreaded Bach Northern disease, where the axle gear would, sooner or later, split from tooth to axle. This seems to be more than that. It is as though whatever is supposed to keep the drivers in vertical position is not operating. I removed the three screws between the drivers, but still could not get into the driver bed. I have momentarily quit at this point. Any comments?
Denis

 

Denis,
E-mail me with what you all noticed on it! I might be able to make a repair to it... Sounds like some tightening up on the gear to driver axle joints needs to be done..... long story...

 

I picked up a 4-8-4 Northern off of Ebay a while back.
When I got it, the back driver wheel kept coming out. The only thing that kept the driver wheel from falling on the ground was the arm.
I found out that the driving wheels only have a small square stub that slides into a white plastic carrier.
On my unit, the white carier had spit and no longer held the back wheel tight.
I placed a little super glue on the square stub and placed it into the white carier.
So far, it seems to be holding ok.
I dont know if this is the same situation as what your having, but your description sure sounds close.

Rich.

 

Rich, I think your right about the problem. I believe these engines developed these two problems; splitting of the drive gear, and splitting at the axle/wheel attachment point. I decided to send the engine back to Bach. I now have four of these little jewels, and a bottle of super glue at the ready.
Denis

 

Actually, I have found another Bach engine doing the same axle split.
They are both 4-8-4 Bachs and they are both Spectrums.
The one I mentioned above is a 4-8-4 Northern wearing Southern Pacific.
I was looking at another one of my Bach 4-8-4's last night, and it has a small split in the axle as well. However, the split has not progressed to the point of breakage.
This is a Bach 4-8-4 J (also spectrum) wearing the Norfolk colors for passanger service.

Rich.

 

The Bachmann 4-8-4 J has a problem with the driver wheels that make it shimmy from side to side. It is actually a spacer problem, as their tolerances are not that tight. This can be easily fixed by splitting a Kadee coupler shim to the middle, then flexing it over the axle at the rear driver between the wheel and the frame. Use one red and one grey (I think that's the color), which is one thin and one thinner, on each side, and you will see a marked improvement in tracking. This will also slow down the wear and tear on the axles and the small plastic parts that hold it all together.

 

Hello...
I'm new to this board, but have been answering questions about the Bachamnn Northerns on the Bachmann web site for a while.
I saw this post and thought I might give some info on 'Bachmann Northern Disease' or 'BND' from here on out. I laughed when I read that as I hadn't seen it given a name before, and I like it.

Anyway, 'BND' usually starts due to a valve gear or side rod bind up. Either something in the valve gear gets/is bent and locks up against something else, or a side rod is clamped too tight against a driver and won't turn. The motor (not knowing there's a problem of course) will keep torquing on that 3rd axle gear until it thows the whole rest of the driver assembly out of alignment. If power isn't pulled away after that happens, eventually the motor could break the axle gear. If you get it stopped as soon as you see something's wrong, you may be lucky enough to remove the cover plate, straighten the drivers back out, locate the source of the bind, clear it and be back in business. How easy this is depends on which version of the Northern you have.
The older 'white boxed' ones with the sidewinder motors had round axle ends that could slip in a bind. This could throw your quartering out of whack and not be easy to straighten out.
The newer 'Plus' line engines have the above mentioned 'square holes' for the drivers. This stops the slipping issue, and makes it virtually impossible to mess up the quartering as the driver will only go on one of 4 ways, and the position of the side rod will guide you the rest of the way.
I've not found a glue yet that will hold a cracked axle, or keep a slipping driver on. Some work for a while, then give out under the pressure they're under from the motor. Best bet is replacing the axle. If the square kind, you should be able to get them still from Bachmann, as they're still used in the current Niagara and GS4 locos.
The plastic axles are there because the locos are of a split frame design. The wheels have to be separated from each other as both sides pick up rail power and supply it to half of the frame.
There is nothing to keep the drivers in a vertical position. The metal frame has slots in it that the drivers ride in, and there is a plastic cover plate on the bottom - that's it. To get to the driver bed, remove the 3 screws between the drivers. There is also a screw under the cab to take the shell off - this has to be out, too. The trailing truck, cover plate, and pilot truck are all one plastic assembly. Once the screws are out, it's a tight pressure fit. Gently pry and twist or wiggle behind the last driver set and the first and it will come off. It'll seem like you're breaking it, but go slow and it'll come off. Don't let it go flying once you get it off, though, or you'll bust the molded break shoes.
Hope I didn't barge in at all,

Mike

 

Mike, I got a 4-8-4 BND for Birthday in 1984.

Took it out of the box and placed it on the Layout so the family could all see the "new" engine run.

I thought it looked like the front end was tilted up with the cab dragging, but it seemed to be tight, nothing loose, so I applied a little throttle.

It moved about a foot going over a turnout, and we heard a tiny "ping" as the cab passed over the curving rail. ???

It seemed to be moving with a bit of a "Lope" or hop along gait, when suddenly, it stalled. Looking it over, we found the piston rod had fallen out of the cylinder!

It has remained in the box since. Bachmann said there was no warranty on my problem.

My whole family knows to NEVER buy me a Bachmann ANYTHING !!!

 

Hi Watash,
Yep, '84 that would've been one of the old sidewiner/pancake motored round axeled ones that were really bad. I remember taking several of those back to the hobby shop myself due to various problems. The Plus line of the mid 90s greatly improved those problems. If yours is still around, it could be a good candidate for a Bowser kit. Out of curiousity, which engine do you have? As for warranty, did they tell you there's no warranty for that problem in 1984, or recently? I only ask because I would bet if you sent it to Bachmann with $15 repair fee for HO steam engines, you'd probably wind up with a new engine. If it's a GS4 Daylight or a Niagara, they'd just replace it. If it's a Class J, they'd give you a new Spectrum J. If it's one of the Santa Fe, CB&Q or UP ones, you'd be given your choice of a Daylight, Niagara, or J. That's basically what they did for me. I sent in a Plus J that was over 7 years old with no paperwork, and said I just wanted the mechanism repaired. They sent me back a brand new SPECTRUM J. Mind you, that's sending me an engine in a different line with an MSRP of $185 in return for a 7 year old Plus engine with no paperwork that probably was around $80 or so when new. That's a pretty good deal. Since yours doesn't work anyway, it can't hurt to see what they'll do. Don't tell them you got it in '84, just send it in with a note saying you've had this engine for a while and the valve gear is messed up. What are my options and see what they say. Bring it to the attention of Regina Farrell - she's the customer service manager - she's the one to talk to about it.

Mike

 

I've got an old J with the pancake engine that blew out on me too. I never sent it in because I repainted the entire engine to better match the colors of the passenger cars. I guess I'll do it, as the new Spectrum J is pretty freakin nice, except for the shimmying thing that can be fixed with washer shims. Thanks for the help!

 

Thanks Mike. My family bought several engines for presents for me while I was traveling, and now I am finding they are all mostly junk even though they are still new in the box.

I'll try to find Bachmann's address and send it to Regina to see what happens.

 

Good ideas from both of you, but I might stress that because they did it for me, doesn't guarantee they'll do it for everyone - although of late, their CS dept has been bending over backwards to make people happy. Regina is great to deal with and so is Joe K, one of their techs. He helped my fix my valve gear problem over the phone and now it's working again. (I now know the 'secret' of Bachmann's valve gear) Watash, just go to http://www.bachmanntrains.com . There's another forum there ('Ask the Bach-Man', though it's not limited to just Bachmann products), but at the bottom of the page is a bunch of links, one of which is for service. Click there and their phone numbers, email addresses and postal addresses are all right there, plus their hours, and even an email form to ask CS a question right from the site is there. Regina is hard to get a hold of, as she's incredibly understaffed, but if you can leave her a voicemail, she's good at returning calls within a day or two.

Mike