Are you running in a command environment with approximately 18V on the track? These mid-90’s K-Line cabooses weren’t designed for that much voltage constantly on the track. Try to find a bulb with a voltage rating of 18V or maybe even 24V that will fit.
So I typically only run this caboose in conventional mode using a CW-80 because it pairs with my Western Pacific F units which are Williams. That said, I do also have some command locos using my new Base 3 so that is a very good thing to know about those bulbs in constant 18V mode, and it makes sense. Thanks!