Hi Mazpro,
I am a rail fan so any pic with trains in it looks good to me. But I will try to help you see your pics afresh. I'll point out what I think is good about each pic (apart from the train).
The first pic is well composed. The train emergecs from the centre of the pic and flows to the right. This is nice for the eye and mind, giving us an origin and a good view of the subject. There is enough scenry to give us a pretty setting too. A nice 'classic' train pic composition.
Can't think of anything to add about the second pic just now.
The third pic seems to be the technically best photo. Notice the lettering on the orange box next to the coupler. It is very sharp in that photo, but not so clear in the other two photos. Focus must be well selected. Another point is the colour of this pic. It seems a little lighter and sunnier than the other two, though the sky still seems over exposed. The other two pics look like the train is in shadow, while this one seems to bring out a better colour.
I just want to expand on the sky exposure a bit. I think the sun might have been in front of you. If you try to get the sun behind you, the exposure range is easier to handle. This is done by waiting for the right time of day. Time and place are very important in photography, photographers often camping out at a site all night to be there when the light is 'right'. Ofcourse, this is not always possible for subjects like trains, which have timetables to meet.
I could post some of my train pics from my last holiday in Java if you are interested.