first boat project

I just bought a 87' citation because the guy told me the motor and out drive were fine and all it need was the floor rebuilt. but when i took it out for a test drive this happened:
motor choked out when I gave too much throttle too fast
more then two quarts of oil leaked out
and when i tried to slow down it sounded as if it popped out of gear and revved half way to the limiter (if a boat that old has a limiter)

Now none of this happened when we took the boat out for a test drive before i bought it but he said he didn't want to go too far because he didn't have gas.

Can anyone help me out and point me at where to start on this motor.

PS thanks in advance

 

What motor, what outdrive?

 

Also, where did the oil leak out of? I'm assuming crank case oil, but did it come out of the intake, valve cover etc?

 

It sounds like a bad accelerator pump in the carb that makes it bog down. It may also need a complete tuneup. I think you are saying also that when you throttled down the engine revved up. Is that correct?