gamefisher wont stay running

[YamahaRacer447]

My friend has at 1991 (I think) gamefisher 9.9. We replaced the carburator after 6 years of just sitting and also replace the plugs. Was running fine for 2 days but come the third day it just wouldnt stay running. We have been messing with it for about 3 straight nights. It takes about 20 pulls then will fire up and run for about 10 seconds strong, then die off and stall. We started messing with the carb adjustment screw but it still seems to be doing the same thing. We are taking our boats out this weekend so I would like to figure out this problem before then. Any help would be appreciated. Thanks.

(fuel is brand new)