Opp is a total donkey calling station, 83/0/1.8 over 53 hands. How is this line? Fire again on the turn or check behind when the scare card comes?

PokerStars No-Limit Hold'em, $0.25 BB (8 handed) Hand History Converter Tool from FlopTurnRiver.com (Format: FlopTurnRiver)

UTG+1 ($52.75)
Hero ($39.55)
MP2 ($27.35)
CO ($15.65)
Button ($25.15)
SB ($19.80)
BB ($28.10)
UTG ($14.90)

Preflop: Hero is MP1 with K, K.
UTG calls $0.25, 1 fold, Hero raises to $1, 4 folds, BB calls $0.75, UTG folds.

Flop: ($2.35) 5, 6, 8 (2 players)
BB checks, Hero bets $1.5, BB calls $1.50.

Turn: ($5.35) 7 (2 players)
BB checks, Hero checks.

River: ($5.35) T (2 players)
BB checks, Hero bets $4