Turn Line?

Limit: $10/20
5 players.

CO is 18/9/1.2 Usually pretty timid but capable of lagging it up with draws.
SB is 60/17/1.2 his open cap preflop, can only mean AA/KK/QQ, he hasn't even 3 bet me with AK so I doubt it's possible.

Pre-flop: (5 players) Hero is Button with Ah As
UTG folds, CO raises, Hero 3-bets, SB Caps, BB folds, CO calls, Hero calls.

Flop: 7h; 6d; Th (13SB, 3 players)
SB bets, CO raises, Hero 3-bets, SB Caps, CO calls, Hero calls.
Thoughts. I've got the SB beat, but what has the CO got?

Turn: 8h (12.5BB, 3 players)
SB checks, CO checks, Hero ?

Not sure on a turn line here, I think I'm getting check-raised often I'm sure the CO does this with a set or flush with the loose goose in between.
If we bet and get two callers do we bet a rag river card?