1978 Merc 800 (80 hp) starting issues

[hogw1ld]

Hi, i am helping a friend with his boat and need a bit of insight. The engine is a 1978 Mercury 800 (sn: 5003702) 80 hp. last season it ran (intermitently) and it had a flat spot in acceleration that if you did not throttle past the motor would die, i assume this is a carb issue, but on a more serious note, it also had sporatic starting issues. so he took the motor to a boat repair guy and he did a bit of troubleshooting and decided it was the "coil pacK" he replaced it and still no spark. there is power to the key switch to the motor but no spark it is equiped with a thunderbolt ignition. any suggestions would be cool, thanks