2000 502 mag mpi, what kind of memory does the computer box have? hours ? and what else? does it have the vin # on it also ?

No problems here YET!

I was talking to a buddy about looking at a boat for him and I wanted to know if there is any info I can get from hooking up a scan tool such a engine hours and things like that?? For example my boat shows 100 hours on meter but I know the guy who owned it b4 me disconnected the hour meter it was way too low when i bought it but the boat was so clean so I didn't care.

So you mean If I am out at the cove and I leave the key in the ON position it will still run my hour meter ? I thought the motor had to be running ?

It will also have stored how many hours it spent at 1000 r.p.m. intervals. For example

# of hours between 1000-2000 rpm
# of hours between 2000-3000 rpm
# of hours between 3000-4000 rpm
etc

But, I think you can only access this with the Quicksilver Digital Diagnostic terminal.

CAP071, Mine still runs the hour meter with just the key on. I wonder if mine has the hour meter in the ecu. Somehow last year mine was left on all week until the batteries died, so now I have an additional 100 hours. That sucks.

I am not sure, but I know it works with my Quicksilver scan tool.