1990 bayliner 120hp l drive force i/o?

Question

my son was jump starting the boat at the lake after he let the battery run down and for got to disconnect the positive cable on the boat then touched the 2 ends from the truck together short circuited the solenoid plus 2 -30 amp fuses 2 relays and several wires now the accessories are working but for some reason it won't start any ideas on what to try next

Answer 1

Yes.  This motor is the same power head as the outboard.  On the back side of the engine is the "pulse pack."  It controls spark to the coils.  It's prone to failure due to excessive amperage surges, like the one you describe.  An easy check  is to connect a timing light to each cylinder and crank the engine.  If it flashes you problem is elsewhere.  If not!  Well you know!!!  $$$$

Answer 2

get a good boat mechanic to fix it. now dont let your idiot son in the boat again. get him a canoe.