5-10nl marginal play

I am on the cuttoff with A2c and raise to 40. Button makes it 100. I have seen him make big bets with marginal hands but usually folds to big raises.
I call, we are both very deep stacked for the game 5000+.
Both blinds fold.

Flop:
3c 4h 8c

I check, he bets 250, i put him on an overpair that is afraid of getting outdrawn. I raise to 700 (could have waited to CR till turn, thoughts?)

Turn is blank 9d. I lead out 1100. He calls.

River is 4d. I am very confident at this point he has KK or QQ. My thought at the time is that he could fold to another barrel, i could have bet less and made it look like a value bet, but i went allin for about 3600 more. He calls.

The river was my biggest concern, this definately wasn't the strongest opponent at the table, and he just called 1100 so he may feel obligated to call anything.

Thoughts?

[captZEEbo1]

stop bluffing your stack off without a good read. It's "marginal" b/c it's a bad play. He obviously did not believe what you were representing. Just pay to draw if he's not capable of folding overpair for 500bb's...also fold preflop.