Samsung Projection TV going Green

Last month I invested $300, against my wife's advice,  in a 6 year old used Samsung HCL4715W projection TV for my kids. It worked fine for two weeks then decided to go green! The first time my kids noticed it, I turned it off and unpluged it for the night and next day it worked fine, but since then it's having increasing green tint, otherwise all colors seem to be ok. The tint is all over the screen. I ran the perfect focus feature with no help. manual convergence screen showes green shadow on the right side of the crosses for both Red and Blue. When I switch to Video the screen starts blue but then turns greenish. I tried to adjust the colors, or the tint but it does not seem to affect the problem. The brightness is still good. I can tell from the air comming out of the TV that it's hot from the inside, and I assumed that that's normal, there is no smoke.. so far! I called the previous owner and he said he had the TV serviced 2 years ago to replace a "convergence Module"? I'm no TV expert, but calim to be handy. Can you tell me please if this is something I can fix on my own, if not is it worth it to have it fixed at the shop.