Nut flush c/raised on river, value in shoving?

[pikeamus]

Villain is loose passive preflop no reads post flop and not enough hands for stats. I often double barrel on friendly turns like this one but decided not to until I know if this guy floats OOP. On river is there any value in raising (shoving) over his bet? Having trouble putting him on a range...

Full Tilt Poker, $0.25/$0.50 NL Hold'em Cash Game, 6 Players
LeggoPoker.com - Hand History Converter

CO: $42.80
BTN: $13.75
SB: $68
BB: $50.40
Hero (UTG): $50
MP: $58.25

Pre-Flop: A[img]/images/graemlins/diamond.gif[/img] Q[img]/images/graemlins/diamond.gif[/img] dealt to Hero (UTG)
<font color="red">Hero raises to $1.75</font>, 4 folds, BB calls $1.25

Flop: ($3.75) 5[img]/images/graemlins/spade.gif[/img] K[img]/images/graemlins/diamond.gif[/img] J[img]/images/graemlins/club.gif[/img] (2 Players)
BB checks, <font color="red">Hero bets $2.80</font>, BB calls $2.80

Turn: ($9.35) 4[img]/images/graemlins/diamond.gif[/img] (2 Players)
BB checks, Hero checks

River: ($9.35) J[img]/images/graemlins/diamond.gif[/img] (2 Players)
BB checks, <font color="red">Hero bets $8</font>, <font color="red">BB raises to $16</font>, Hero ???