1976 75 hp Idle in gear problem

[CaptNemo]

I have a 1976 Johnson Stinger 75 hp model 75ELR76D, the motor runs fine in neutral but when i drop it in gear just on idle, it will run a minute or so then the rpms go down and the motor will shut off like its starving for fuel, it will restart again after a little choke. After feathering the throttle and quick push on key choke, it will run good on the high end when it gets past the idle . I rebuilt the carbs and fuel pump and replaced all the fuel lines and its better but still will stall after a short time. My thought is to rebuild the carbs again or replace the idle orifice and core plug as noted in the boats.net diagram for my motor (What tool is needed to remove the orifice). It has good spark and compression. Any help would be appreciated. Thanks Mike

[boats.net]

Yes sounds like there is a plugged air or fuel passage somewhere. The idle orfice can be removed with a standard screw driver. Be sure to verify all passages are clear before reassembly