please help

[huntingtheworld]

i got a 1972 Johnson 65 hp power shifter and i got a few random holes in the intake i think.it looks like a intake but it is where the piston rod barrens are.the motor has grate compression and run like junk.someone has rebuilt the motor before but i was wondering if something could of came apart and i may not know it or maybe did someone blow it up and rebuilt it and did not see the holes. it still runs but I'm trying to figure out how thay got thair.
i have not took it apart cause i think someone didn't see the holes.thair are 3.it looks like it got under 2 much presser and exploded. oh and by the way thay are all on the middle cylinder.i am new to owning a boat and tell me what Yall think.
thanks Jason