Coupler probklens

[ralph67]

Two of my cars uncouple ever time it passes over a switch or slight bump.. I have noticed their couplings are lower than the mating couplings on the other cars.Is this fixable ?If so how.? Being new top the hobby, I thought the coupling heights would be standard.

[James in FL]

Droopy couplers are not an uncommon problem, and usually a very easy and quick fix.

Need a little more information;
1)   What type and what brand couplers are you having troubles with?
2)   What is the brand (manufacturer) of the problem child cars?
3)   What is happening when traversing the switch? Are the wheels bumping up on the points, or are the wheels dropping into the flange way at the frog? Or are they possibly riding up on the flanges as if the flange way is not deep enough and the wheel tread is losing contact with the railhead? If your couplers have trip pins, are they catching on anything?

You will have to get your eyes down low to the railhead, and run very slow, to observe what is actually happening.

4)   Are all your wheelsets, on the problem child rolling stock, the same diameter (33 or 36in.)?
5)   Do you have a coupler height gauge?
6)   Does this happen regardless of the direction of travel over the turnout?
7)   Are you adding additional weight to your rolling stock?

The more information you can provide to us, the more accurate the solutions suggested will be.

[ralph67]

One  problem car is an Atlas. Your note has caused me to look at the car more closely and I found one set of trucks has larger  diameter wheels than the other.When I couple the larger set to the previous car ,the problem is solved. I bought the car used . Lesson learned.
I did not know there were two wheel sizes.
The second car may have the same problem. It is the old style hook coupler . I don't know the car mfg. I bought this car used because i needed that style coupling to hook up with a new engine returned to me by Bachmann ,
I will study the other suggestionsyou made for troubleshooting & follow up woith you if I gfind anything.
Thak you for your help . I really appreciate it.after I sent in an engine to be repaired. I thought I would change one coupling on this car to the knuckle type so I could pull my other cars which were Bachmanns.

[James in FL]

You are welcome, glad I could offer some possible solutions.

Good to hear you are making positive progress with this.

Don't want to fill you with information overload all at one time, so I will await your reply on your observations on the second car.
Usually the manufacturer of the car will be embossed on the underside of the chassis.

One more question, what is the root cause of the "slight bump" with your track work?
These types' bumps can, and should, be eliminated.