Please, it's bugging the crap out of me. This is what I remember about it. It came out in the 1980's ... The story involves a boy there's a swamp and a mechanical monster in the swamp. He thinks it's a monster until the end, when we find out it's an old steam machine (some sort of digger/excavator). THat's the main story line, what is this movie called????

Right. Very difficult movie for me to place. I've tried to come up with the name of this movie for years in my head. There's a word like Donk-A-Jen that the boy hears or says or something. I'll be able to find out. Hold on...

http://www.imdb.com/title/tt0091810/

hey i know that movie that kid from et , he builds that bike that ride on the train tracks

Thank you so much. I remember it as "The Quest". I can't believe you knew it. I even remember him hearing the voice "Donkajen". Like I said in the first post, those are the things that really stuck out that I remember. Thanks again!

I think it also sounds like Iron Giant. It's a cartoon.