1845c keeps blowing a fuse

I have a 1999 1845c with 3400 hours on it. Keeps blowing a fuse and the engine shuts down immediately. Engine cranks but no start. Found the fuse block below the seat. Four fuses in a row (all 30 amp-though that was kinda strange). One was blown. Replaced it and the engine fired right up. Ran it for a few hours and same problem, only now it blows with in a minute or less. I've looked for a shorted wire, can seem to find one. I could really use a wiring diagram just to see what this...

1845c keeps blowing a fuse

1845c keeps blowing a fuse