Your line is definately too short, that is why you have foam. You need at least five foot of 3/16 inch vinyl beer line to get the right amount of resistance to the flow and stop your foam problems. Dont worry if you have extra line in the system coiled up, we all do. Just make sure not to close the line in the door or anything. Here is a link to where you can get the line.
http://www.micromatic.com/draft-keg-...s-cid-365.html
Semper Fi,
The Gunns
"Beer is proof that god loves us and wants us to be happy" - Benjamin Franklin