yamaha 30hp outboard fuel problem

[smoothjonnyb]

I have an early 1980's 30hp yamaha outboard, it runs sweet then seems to be starved of fuel and after 30 seconds runs really rough. It's a 3 cylinder with a fuel pump attatched to the carbs, has anyone had similar problems?? I am going to replace the fuel pump diaphrams would this help?

thanks

[boats.net]

Probably need to remove and clean carbs and replace fuel pump diaphrams.