I have a C&O K-line coal car and have had lots of trouble with one of the couplers opening up on curves when there is even only a few cars behind it. Ideas?
It sounds like it has a weak spring holding the pin in place. Can you tie it off?
I have an MTH reffer that was doing the same thing. Come to find out, the die cast coupler wasn’t closed all the way. They take more force than the plastic ones. If that’s not your problem, Lionel sells die cast replacement trucks with couplers. Two different styles to choose from. Replace the trucks.
Jim
The problem appears to be in the trucks but I have solved the problem by replacing the K-Line reease with a Lionel release pin looks the same except that the Lionel pin is about 1/64 of an inch longer and holds the coupler in better. Like jaabat mentioned you can always change the trucks out to Lionel.
Lee in West Palm Beach FL