Mercury 70 starts hard

[10at6]

This is a 3 cyl 1989 0r 1990 model Seems like every year it needs to crank a bit longer to start. Once it starts it runs great and subsequent starts are very easy. The enricher valve seems to work as it will choke the engine when warm. Seems like it's not getting enough fuel during the start cycle. Seems like if you let it set for a few minutes after cranking it sometimes will fire right up. I always lower the motor to vertical before trying and pump the bulb up hard
any ideas appreciated
thanks
Randy

[boats.net]

Check compression, Check spark at plugs when cranking over, if haven't cleaned carbs and check intake gaskets may need it.