Large Scale Central

Bachmann Connie Bouncing?

General Discussion
#1

I recently bought this Connie in a small collection and after replacing the main gear with the Bachmann metal one I had it on the track today and found it has a bounce to it.

I tested this with my other Connie and it doesn’t have the bounce? The wheels are level. It looks like all the springs are present but when moving forward or back and stops it bounces like a bobble head?
Could the springs be worn out?

Any ideas what could be wrong with it?

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Here is a video if it will work here.
https://www.facebook.com/100000657514790/videos/pcb.3949617551955851/786828000541119

#2

Didn’t work. Page says it’s being shared with a small group

#3

I get a message the video isn’t available any longer.

#4

You will probably find that one of the drivers on the axel you replaced is out of quarter with the other drivers…that would cause the bouncing action…this causes the side rods to be out of sinc…

#5

missing or collapsed springs on the DRIVERS, not the pilot

#6

I was going to say “out of quarter” but FR Fred beat me to it. :grinning:

#7

Some grit in the gear case?

#8

Maybe post the video on Youtube?

#9

The video shows the issue but posting is an issue :upside_down_face:
Basically it runs back and forth okay but when it stops it bobs/tips forward and does the same when reversing and stopping. it bobs backwards.

I’m going to check the springs and the quarter today.
I might even swap out the pilot from the other Connie to see if that is the issue.

1 Like
#10

I would think that if it was quartering it would pogo all the time not just at a stop.
It would seem that it is suspension, either springs or retainers, weight on pilot truck, or balance point in the center causing the teeter totter effect.
Can you manually create the effect when stationary?

Just some thoughts

#11

A couple of other things to check, deep dive but you never know. are all the springs the same, or have some been replaced? are all the factory weights installed? i know on my loco i had to change the rear weight significantly (replaced with stick on’s) when i installed the Barry gearbox, and if that is the case maybe the rear weight is missing?

Al P.

1 Like
#12

That is what I was thinking. If it was out of quarter it would bind up when moving but I’m going to take a closer look at that just in case.
The wheels appear to be level with each other on the track and upside down in the box.
I was thinking that a middle set could be higher than the others and cause a see saw.

When the loco is stationary I can press down on the front or back and create the same bobble head teeter totter.

#13

FIXED IT! Thanks to all that chimed in with ideas.

The pilot spring was okay. The quartering was okay. The 4 springs on the drive axle looked fine but just in case I swapped them with the rear axle but the problem persisted.
The issue was the drive axle was not depressing that tiny fraction when placed on the track causing the whole loco to teeter totter on those wheels.
The reason for this was that after replacing the drive gear I put the journal bearing boxes on backwards. They look identical but on one side there is a tiny little groove that I thought was from the manufacturing process. I looked at the others and that groove was facing in when it should have been facing out.

I still don’t see a difference but whatever it was it was not allowing that journal box to depress that 1/32 of an inch it needed to.

I got it back together and just gave it a test go in the main yard and it is smooth.

Thanks again guys.

In the photo you can see that little groove.

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526552753_24712761721662403_6239746339007340734_n1920×1440 187 KB

1 Like
#14

I honestly see the difference Todd. I’m thinking the groove/rabbet is probably intentionally molded so it will be noted to go to the outside upon assembly. The u-channel is offset looking at that picture. It’s tricky but it’s there.

Either way glad it’s fixed.