Carbs leaking and motor runs but then doesn’t

[Bke12345]

Hey all. So I got a 1977 Mercury 150 power of tower. First of all I finally got the motor to start after I put some money into it. New everything, literally! So got the motor running but carbs are leaking out of the all 3 jets and I just replaced all 3 carb gaskets. I soaked the carb in parts cleaner for couple days. The motor pops and bogs like it wants to start then after missing with the throttle alittle and choke it starts, still the carbs drip after it’s running. So question is, could that be the reason the motor struggles to start and could there be a reason for the carbs to be leaking even though I changed all the gaskets?
thanks

 

[Bke12345]

Floats are new by the way and I replaced the gasket inside the bowl side where the needles are

 

[Chris1956]

New inlet needles and seats are a good idea. Not all inlet needle seats use gaskets. You will need to look at the seat and see if it is too high for proper float adjustment.

Carbs should be set a 1-1/2 turns open for initial setting. They will need to be adjusted on the water with the motor warm.

Check the timing. With the carbs still closed, but ready to open, timing should be 4-6*BTDC. max spark advance is 21*BTDC.

A service manual is a real good idea.