93 regal tensioner came off!

While removing my serpentine belt to better reach the PS pump, my tension pulley popped off. It's the type where you use a 3/8 socket to rotate it and give slack to the belt. I must have rotated too far because now I have a spring and the pulley in my hand. Anybody know how to get it back on properly? Every time I think I have it right it pops back off- How exactly does it hold togther? Thanks in advance!

Those are factory pressed together-- yours is busted- must have been bad for awhile- rattling and making noise- I have had this happen to me- go buy a new one- from any parts store.......