Live 3/6 Kill hand with maniac

[tacoshooter]

My first SS post:

Maniac is UTG, in the kill (game is playing $6/$12) and has raised the last 20 hands preflop. He's showing down crap to the river and winning lucky more often than not. Up about $1,200 on his $100 buy-in. No kidding.

This is the hand I was thinking about on the drive home:

Preflop:

I'm in MP with A7s. Maniac makes it $12 to go UTG. Three folds to me, I re-raise to $18. Folded to maniac. He calls.

I'm thinking I'm way ahead against his average hand and when it's folded to me I'm sure I can get it heads-up so I raise. His call was a little perplexing because he had been re-raising nearly 100% of the time in the past -- but I have to think it's because I'd come after him with good hands a couple times (and lost [img]/images/graemlins/frown.gif[/img]). He mutters something to his buddy like "I gotta call with a pocket pair!" as he throws in. He's a talker.

Flop:

Flop comes 284. Suits unimportant. Maniac throws in $6. I think for a bit and call.

Maniac would bet at this point with anything so I can't put him solidly on a hand. I know my ace is good and I'm pretty certain my 7 would be good too. But he might have caught a piece of that board or really have a small PP.

Turn:

Turn is a 7, pairing me. Maniac bets. I quickly call.

He's talking up a storm. I'm fully in maniac-call-down mode but I felt really, really weak here.

River:

River is a blank. Maniac bets. I call.

Okay, so how did I do? This was definitely an out-of-the ordinary situation for me. I just had no idea where I was at with this guy because he only had one move. Bet, and if raised, re-raise. Is call-down mode appropriate for a good-but-not-great hand here against a psycho?

Let me have it.

[House-Lion]

Seems fine to me, but A7s might have been slightly to small to catch a maniac.

[tacoshooter]

Interesting. Maybe I was off base from the start.

I figured A7s would be in the zone given that he was seeing every flop and had shown down crap (albeit winning crap) on the previous set of hands. Had anyone called before me or if I wasn't certain I could fold everyone else out with a raise, I would have passed.

If A7s isn't good enough in this situation, what would be the cutoff?