I understand why a cooling fan can be needed. Other brands of decoders get hot when trying to handle higher powered G scale stuff. That's a reason I stayed with MTH in my stuff.
I have run in the hot summer outside with my G scale. I've never had a problem with overheating even in the sun. Maybe I've just been lucky. I do run extra engines on heavy trains.
I would think engines like the MTH G scale Triplex might have this issue. I haven't seen it personally.
So, I just wonder if it's needed in O scale very often? I can understand it when needed.
I remember some posts on a G scale forum about MTH changing a solid motor mount cover (GS4?) to allow for better cooling of the motors.
