Brake problems-

This van has been good but has been sitting for awhile. I drove it the other day with a lot of hay bales in it and the brakes went out. Found out there was a back break fluid leak. Line was replaced by a competant person. The problem is that the brakes remain spongy after extensive careful bleeding procedures. The only other major component known since my husband passed away and he basically maintained this van, is that I remember several years ago he got fed up with the ABS sueste, and disconnected it. He was an electrician and farmer and sort of did what he wanted at times. Any suggestions would be appreciated.