Hello All,
I just picked up a Rivarossi 4-8-8-4 at a show. she runs like a top, But, the last 4 arrangement seems to rock the boiler area in the back from the cab to the front. especially at slow speeds.
Now I looked at the hing, it has the spring there. and the lock nut. The Driver wheels are all ok, in fact i replaced them with new ones I had in my stock. so it seems to be ok in that respect. But I cant for the life of me, figure out why it rocks like a drunk??
Anyone have a clue? or have had the same problem? , or a suguestion to fix the problem?? I can explaine more if need be. but I think you get the jest of the idea of what it is doing.
Thanks in Advance
I’m not sure I follow you, but I would guess that your track may be as much to blame as the loco. I don’t see how the rear truck could be faulted without the twin banks of drivers having a big say in it.
Are you positive all axles are truly seated in their bearings? Are all wheels in gauge? Are the flanges of every wheel in line with the others when the axles are pressed left and right?
Is it a newer production Big Boy? Often on the older Rivarossi articuateds the trailing truck (the lead truck on the Cab Forward also) is mounted to the power truck and not the frame so I would check the power trucks first.On the older Rivarossi articulateds the drive shaft from the motor goes to the upper gearbox with another shaft going to the front gearbox, in addition to these shafts both gear boxes also have a shaft that passes down through the frame to meet up with drive trucks (for lack of the proper name). On the older engines these shafts end with a ball that has 2 shafts that stick out either side which fit into receiving slots in power truck’s shafts, if they don’t meet up properly in both slots that can cause a rocking motion, if it isn’t so bound up that it doesn’t run at all or even sit properly. Also check all of the drivers, side rods and valve linkages to make sure everything is in position and nothing has been tweeked inadvertantly by you or possibly a hidden problem from the former owner. You would be surprised at how easily these articulateds can be sidelined by some minor piece. Once you get it all squared away and get it running you’re gonna LOVE it!
Yes they are fine. I even hand held it into place to run it, and the boiler part bounces like crazy, at first i thought it might be the drive linkage, but the 8 drive wheels sit on the track ok, I dont see the set moving off of the track at all.
I have a flex code 100 hand laied to a 2x4 with the power to it so i can fix anyting prior to being on a main line .
To me, It almost feels like there is a sort of bump or someting making the boiler section go from side to side . aqlmost like something is binding it to a point and making it bump the boiler section from side to side itself.
The axels are fine,and seated well. now for your question "Are the flanges of every wheel in line with the others when the axles are pressed left and right? now with that in mind. no, not even on my Challengers, or Y classes. and they run perfectly.
You may have remounted the drivers out of quarter. When that happens, the valve gear jams or binds on one side, and the entire boiler will appear to lurch, maybe buck. Also, could you have forgotten a screw that attaches the boiler to the frame?
On some Rivarossi articulateds, I know the older ones for sure, not all driver axles had bearings. Seems like one inner axle just ran in a slot. If that axle got dirty, or any of the linkage on that engine got to where it was even slightly binding, that driver would hop causing what you are seeing. I had to cobble up some bearings.
But, as noted above, it sure sounds like a driver out of quarter. Did you roll the rear engine up and down the track with your finger when it was separated from the rest of the engine? If not try that, and that should get you a lot closer to the problem. If that engine is smooth by itself, then the problem is likely in the drive components coming to it. Remember, if it rocks in forward only you may only see it pushing it backwards with your finger. Let us know how you do. Good luck.
I think i just found it, after taking the advice of all of you. I went and re checked things. and just out of curiosity took out the gear box, did some manual turning of it. and found that the shaft for the drive wheel gear box, to the top boiler link was bent. I replaced it with a new one just now and low and behold. no more rocking.
What a pain in the**** that was. but if I didnt ask, I would have been racking by old brain forever on this one. I am just happy I have a stock of Rivarossi parts here to do some replacing if need be. now to get another one. and pay through the nose for it. LOL
Thanks all. I appreciate you all helping me with this one. now maybe i can get a few hours of sleep seeing it is almost 6 am. Oh well, thats the fun of model railroading. sometimes you have to pull your hair out to get things to work. then ask. then pull again.
sort of funny too, the number of the big boy is 4013 LOL