3bet jam this river?

[sublime]

i mean i know its rare that he runna runna a ace high flush, but i am just checking if jamming here is correct.

no stats on villain, i am in the 20/17 range

Full Tilt Poker - No Limit Hold'em Cash Game - $0.50/$1 Blinds - 5 Players - (LegoPoker HH Converter)

SB: $65.00
<font color="black">Hero (BB): $121.70</font>
UTG: $39.00
CO: $93.00
BTN: $115.35

<font color="black">Preflop:</font> Hero is dealt K[img]/images/graemlins/heart.gif[/img] J[img]/images/graemlins/heart.gif[/img] (5 Players)
UTG folds, <font color="red">CO raises to $3.00</font>, 2 folds, Hero calls $2.00

<font color="black">Flop:</font> ($6.50) 9[img]/images/graemlins/heart.gif[/img] Q[img]/images/graemlins/diamond.gif[/img] J[img]/images/graemlins/diamond.gif[/img] (2 Players)
Hero checks, CO checks

<font color="black">Turn:</font> ($6.50) 3[img]/images/graemlins/heart.gif[/img] (2 Players)
<font color="red">Hero bets $6.00</font>, CO calls $6.00

<font color="black">River:</font> ($18.50) 8[img]/images/graemlins/heart.gif[/img] (2 Players)
<font color="red">Hero bets $12.00</font>, <font color="red">CO raises to $28.00</font>, <font color="red">