Think it's ok but wanted to check anyway:

2 folds, I raise to 3.5$ in Cutoff with [Ac] (162$). Button and Big blind (122$) calls.

Flop: [9h][5c] - 11$. Big blind checks, I bet 8$, Button folds, big blind calls.

Turn: - 27$. Big blind checks, I bet 20$. He thinks for a bit then calls.

River: - 67$. Big blind leads 20$. Feels like a weak blocking bet with a J to me. I reraise to 65$.

Thoughts?

I dun no..u need to have some read on his play..im my exp only few villians actually send out blocking bets on 100s and even if it is..i doubt that Jx is calling 65 here..it depends if u bet draws...if u do and villian is observant i would consider pushing to represent missed draw as some sort of value bet

Fine by me...you're folding to a push obv.

Calling is also fine, but if you think it's a block, then the raise is fine.

small block bet, i agree, but with no reads, i just call the $20.